diff --git a/libc/src/.clang-tidy b/libc/src/.clang-tidy
index b21d4c3928c8f..1c79b1cf6aae6 100644
--- a/libc/src/.clang-tidy
+++ b/libc/src/.clang-tidy
@@ -1,5 +1,5 @@
 InheritParentConfig: true
-Checks: '-*,llvmlibc-*,readability-identifier-naming'
+Checks: '-*,llvmlibc-*,readability-identifier-naming,llvm-header-guard'
 HeaderFilterRegex: '.*'
 WarningsAsErrors: 'llvmlibc-*'
 CheckOptions:
diff --git a/libc/src/__support/CPP/algorithm.h b/libc/src/__support/CPP/algorithm.h
index 6b17f58ea4624..6ce56a9f35659 100644
--- a/libc/src/__support/CPP/algorithm.h
+++ b/libc/src/__support/CPP/algorithm.h
@@ -9,8 +9,8 @@
 // they prove useful.
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_ALGORITHM_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_ALGORITHM_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_ALGORITHM_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_ALGORITHM_H
 
 #include "src/__support/macros/attributes.h" // LIBC_INLINE
 
@@ -28,4 +28,4 @@ template <class T> LIBC_INLINE constexpr const T &min(const T &a, const T &b) {
 } // namespace cpp
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_ALGORITHM_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_ALGORITHM_H
diff --git a/libc/src/__support/CPP/array.h b/libc/src/__support/CPP/array.h
index 52e6f1152e78f..1cdc8b7d7e79b 100644
--- a/libc/src/__support/CPP/array.h
+++ b/libc/src/__support/CPP/array.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_ARRAY_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_ARRAY_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_ARRAY_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_ARRAY_H
 
 #include "src/__support/macros/attributes.h"
 #include <stddef.h> // For size_t.
@@ -52,4 +52,4 @@ template <class T, size_t N> struct array {
 } // namespace cpp
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_ARRAY_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_ARRAY_H
diff --git a/libc/src/__support/CPP/atomic.h b/libc/src/__support/CPP/atomic.h
index 6922a367289a9..609aac31252e0 100644
--- a/libc/src/__support/CPP/atomic.h
+++ b/libc/src/__support/CPP/atomic.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_ATOMIC_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_ATOMIC_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_ATOMIC_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_ATOMIC_H
 
 #include "src/__support/macros/attributes.h"
 #include "src/__support/macros/properties/architectures.h"
@@ -118,4 +118,4 @@ LIBC_INLINE void atomic_thread_fence(MemoryOrder mem_ord) {
 } // namespace cpp
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_ATOMIC_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_ATOMIC_H
diff --git a/libc/src/__support/CPP/bit.h b/libc/src/__support/CPP/bit.h
index f64473c211299..4e4205db9128b 100644
--- a/libc/src/__support/CPP/bit.h
+++ b/libc/src/__support/CPP/bit.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SUPPORT_CPP_BIT_H
-#define LLVM_LIBC_SUPPORT_CPP_BIT_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_BIT_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_BIT_H
 
 #include "src/__support/CPP/type_traits.h"
 #include "src/__support/macros/attributes.h"
@@ -61,4 +61,4 @@ LIBC_INLINE constexpr To bit_or_static_cast(const From &from) {
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SUPPORT_CPP_BIT_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_BIT_H
diff --git a/libc/src/__support/CPP/bitset.h b/libc/src/__support/CPP/bitset.h
index 5ddbea27c7d54..bae71d84314e6 100644
--- a/libc/src/__support/CPP/bitset.h
+++ b/libc/src/__support/CPP/bitset.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_BITSET_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_BITSET_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_BITSET_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_BITSET_H
 
 #include "src/__support/macros/attributes.h"
 #include <stddef.h> // For size_t.
@@ -87,4 +87,4 @@ template <size_t NumberOfBits> struct bitset {
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_BITSET_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_BITSET_H
diff --git a/libc/src/__support/CPP/cstddef.h b/libc/src/__support/CPP/cstddef.h
index 17568335d9d89..4c5c4a492ba42 100644
--- a/libc/src/__support/CPP/cstddef.h
+++ b/libc/src/__support/CPP/cstddef.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_BYTE_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_BYTE_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_CSTDDEF_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_CSTDDEF_H
 
 #include "src/__support/macros/attributes.h"
 #include "type_traits.h" // For enable_if_t, is_integral_v.
@@ -68,4 +68,4 @@ to_integer(byte b) noexcept {
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_BYTE_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_CSTDDEF_H
diff --git a/libc/src/__support/CPP/expected.h b/libc/src/__support/CPP/expected.h
index 2fdcc5246d473..c20d100f8cf82 100644
--- a/libc/src/__support/CPP/expected.h
+++ b/libc/src/__support/CPP/expected.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SUPPORT_CPP_EXPECTED_H
-#define LLVM_LIBC_SUPPORT_CPP_EXPECTED_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_EXPECTED_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_EXPECTED_H
 
 namespace __llvm_libc::cpp {
 
@@ -48,4 +48,4 @@ template <class T, class E> class expected {
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SUPPORT_CPP_EXPECTED_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_EXPECTED_H
diff --git a/libc/src/__support/CPP/functional.h b/libc/src/__support/CPP/functional.h
index 5ddb988d33125..6c33b55db3700 100644
--- a/libc/src/__support/CPP/functional.h
+++ b/libc/src/__support/CPP/functional.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_FUNCTIONAL_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_FUNCTIONAL_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_FUNCTIONAL_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_FUNCTIONAL_H
 
 #include "src/__support/CPP/type_traits/enable_if.h"
 #include "src/__support/CPP/type_traits/is_convertible.h"
@@ -67,4 +67,4 @@ template <typename Ret, typename... Params> class function<Ret(Params...)> {
 } // namespace cpp
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_FUNCTIONAL_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_FUNCTIONAL_H
diff --git a/libc/src/__support/CPP/limits.h b/libc/src/__support/CPP/limits.h
index 46a1172c28502..4e76337a2445e 100644
--- a/libc/src/__support/CPP/limits.h
+++ b/libc/src/__support/CPP/limits.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_LIMITS_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_LIMITS_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_LIMITS_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_LIMITS_H
 
 #include <limits.h>
 
@@ -98,4 +98,4 @@ template <> class numeric_limits<__uint128_t> {
 } // namespace cpp
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_LIMITS_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_LIMITS_H
diff --git a/libc/src/__support/CPP/new.h b/libc/src/__support/CPP/new.h
index 4a5fb7123083b..14ee0ab2bbc0d 100644
--- a/libc/src/__support/CPP/new.h
+++ b/libc/src/__support/CPP/new.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_NEW_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_NEW_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_NEW_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_NEW_H
 
 #include "src/__support/common.h"
 
@@ -99,4 +99,4 @@ void operator delete[](void *, size_t) noexcept
 void operator delete[](void *, size_t, std::align_val_t) noexcept
     __asm__("__llvm_libc_delete_array_sized_aligned");
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_NEW_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_NEW_H
diff --git a/libc/src/__support/CPP/optional.h b/libc/src/__support/CPP/optional.h
index 07cc1d2adac65..b5e2ef7c8bc2f 100644
--- a/libc/src/__support/CPP/optional.h
+++ b/libc/src/__support/CPP/optional.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_OPTIONAL_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_OPTIONAL_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_OPTIONAL_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_OPTIONAL_H
 
 #include "src/__support/CPP/type_traits.h"
 #include "src/__support/CPP/utility.h"
@@ -120,4 +120,4 @@ template <typename T> class optional {
 } // namespace cpp
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_OPTIONAL_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_OPTIONAL_H
diff --git a/libc/src/__support/CPP/span.h b/libc/src/__support/CPP/span.h
index b7828abe8feef..ebf637c5d2667 100644
--- a/libc/src/__support/CPP/span.h
+++ b/libc/src/__support/CPP/span.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_SPAN_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_SPAN_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_SPAN_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_SPAN_H
 
 #include <stddef.h> // For size_t
 
@@ -121,4 +121,4 @@ template <typename T> class span {
 
 } // namespace __llvm_libc::cpp
 
-#endif /* LLVM_LIBC_SRC_SUPPORT_CPP_SPAN_H */
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_SPAN_H
diff --git a/libc/src/__support/CPP/string.h b/libc/src/__support/CPP/string.h
index be7ed41ffcdce..2f60720e93450 100644
--- a/libc/src/__support/CPP/string.h
+++ b/libc/src/__support/CPP/string.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_STRING_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_STRING_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_STRING_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_STRING_H
 
 #include "src/__support/CPP/string_view.h"
 #include "src/__support/integer_to_string.h" // IntegerToString
@@ -227,4 +227,4 @@ LIBC_INLINE string to_string(unsigned long long value) {
 } // namespace cpp
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_STRING_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_STRING_H
diff --git a/libc/src/__support/CPP/string_view.h b/libc/src/__support/CPP/string_view.h
index 1b47c2bc1f3c9..d494325def3bf 100644
--- a/libc/src/__support/CPP/string_view.h
+++ b/libc/src/__support/CPP/string_view.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_STRINGVIEW_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_STRINGVIEW_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_STRING_VIEW_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_STRING_VIEW_H
 
 #include "src/__support/common.h"
 
@@ -199,4 +199,4 @@ class string_view {
 } // namespace cpp
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_STRINGVIEW_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_STRING_VIEW_H
diff --git a/libc/src/__support/CPP/stringstream.h b/libc/src/__support/CPP/stringstream.h
index 089483147e6a5..0a92ddae66c64 100644
--- a/libc/src/__support/CPP/stringstream.h
+++ b/libc/src/__support/CPP/stringstream.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_STRINGSTREAM_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_STRINGSTREAM_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_STRINGSTREAM_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_STRINGSTREAM_H
 
 #include "span.h"
 #include "string_view.h"
@@ -92,4 +92,4 @@ class StringStream {
 } // namespace cpp
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_STRINGSTREAM_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_STRINGSTREAM_H
diff --git a/libc/src/__support/CPP/type_traits.h b/libc/src/__support/CPP/type_traits.h
index 3de2ca5890318..1eb2f34ebee37 100644
--- a/libc/src/__support/CPP/type_traits.h
+++ b/libc/src/__support/CPP/type_traits.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_H
 
 #include "src/__support/CPP/type_traits/add_lvalue_reference.h"
 #include "src/__support/CPP/type_traits/add_pointer.h"
@@ -58,4 +58,4 @@
 #include "src/__support/CPP/type_traits/type_identity.h"
 #include "src/__support/CPP/type_traits/void_t.h"
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_H
diff --git a/libc/src/__support/CPP/type_traits/add_lvalue_reference.h b/libc/src/__support/CPP/type_traits/add_lvalue_reference.h
index d07db42aaac36..69d75018fcf2e 100644
--- a/libc/src/__support/CPP/type_traits/add_lvalue_reference.h
+++ b/libc/src/__support/CPP/type_traits/add_lvalue_reference.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_ADD_LVALUE_REFERENCE_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_ADD_LVALUE_REFERENCE_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_ADD_LVALUE_REFERENCE_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_ADD_LVALUE_REFERENCE_H
 
 #include "src/__support/CPP/type_traits/type_identity.h"
 
@@ -27,4 +27,4 @@ using add_lvalue_reference_t = typename add_lvalue_reference<T>::type;
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_ADD_LVALUE_REFERENCE_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_ADD_LVALUE_REFERENCE_H
diff --git a/libc/src/__support/CPP/type_traits/add_pointer.h b/libc/src/__support/CPP/type_traits/add_pointer.h
index 543259ea1ca8f..1ea55b7137fee 100644
--- a/libc/src/__support/CPP/type_traits/add_pointer.h
+++ b/libc/src/__support/CPP/type_traits/add_pointer.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_ADD_POINTER_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_ADD_POINTER_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_ADD_POINTER_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_ADD_POINTER_H
 
 #include "src/__support/CPP/type_traits/remove_reference.h"
 #include "src/__support/CPP/type_traits/type_identity.h"
@@ -25,4 +25,4 @@ struct add_pointer : decltype(detail::try_add_pointer<T>(0)) {};
 template <class T> using add_pointer_t = typename add_pointer<T>::type;
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_ADD_POINTER_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_ADD_POINTER_H
diff --git a/libc/src/__support/CPP/type_traits/add_rvalue_reference.h b/libc/src/__support/CPP/type_traits/add_rvalue_reference.h
index b912cef59b68f..e2a135b3893d8 100644
--- a/libc/src/__support/CPP/type_traits/add_rvalue_reference.h
+++ b/libc/src/__support/CPP/type_traits/add_rvalue_reference.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_ADD_RVALUE_REFERENCE_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_ADD_RVALUE_REFERENCE_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_ADD_RVALUE_REFERENCE_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_ADD_RVALUE_REFERENCE_H
 
 #include "src/__support/CPP/type_traits/type_identity.h"
 
@@ -26,4 +26,4 @@ using add_rvalue_reference_t = typename add_rvalue_reference<T>::type;
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_ADD_RVALUE_REFERENCE_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_ADD_RVALUE_REFERENCE_H
diff --git a/libc/src/__support/CPP/type_traits/always_false.h b/libc/src/__support/CPP/type_traits/always_false.h
index 5e3a51479e3d2..0a633d41598df 100644
--- a/libc/src/__support/CPP/type_traits/always_false.h
+++ b/libc/src/__support/CPP/type_traits/always_false.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_ALWAYS_FALSE_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_ALWAYS_FALSE_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_ALWAYS_FALSE_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_ALWAYS_FALSE_H
 
 #include "src/__support/macros/attributes.h"
 
@@ -26,4 +26,4 @@ template <typename...> LIBC_INLINE_VAR constexpr bool always_false = false;
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_ALWAYS_FALSE_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_ALWAYS_FALSE_H
diff --git a/libc/src/__support/CPP/type_traits/bool_constant.h b/libc/src/__support/CPP/type_traits/bool_constant.h
index 6fcfb8e82e4d8..84a5c76fcde9b 100644
--- a/libc/src/__support/CPP/type_traits/bool_constant.h
+++ b/libc/src/__support/CPP/type_traits/bool_constant.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_BOOL_CONSTANT_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_BOOL_CONSTANT_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_BOOL_CONSTANT_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_BOOL_CONSTANT_H
 
 #include "src/__support/CPP/type_traits/integral_constant.h"
 
@@ -17,4 +17,4 @@ template <bool V> using bool_constant = cpp::integral_constant<bool, V>;
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_BOOL_CONSTANT_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_BOOL_CONSTANT_H
diff --git a/libc/src/__support/CPP/type_traits/conditional.h b/libc/src/__support/CPP/type_traits/conditional.h
index f9917c2a7264c..431ccb2a483fc 100644
--- a/libc/src/__support/CPP/type_traits/conditional.h
+++ b/libc/src/__support/CPP/type_traits/conditional.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_CONDITIONAL_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_CONDITIONAL_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_CONDITIONAL_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_CONDITIONAL_H
 
 #include "src/__support/CPP/type_traits/type_identity.h"
 
@@ -22,4 +22,4 @@ using conditional_t = typename conditional<B, T, F>::type;
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_CONDITIONAL_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_CONDITIONAL_H
diff --git a/libc/src/__support/CPP/type_traits/decay.h b/libc/src/__support/CPP/type_traits/decay.h
index f3f9cfc5eaa00..0961fd1c3689b 100644
--- a/libc/src/__support/CPP/type_traits/decay.h
+++ b/libc/src/__support/CPP/type_traits/decay.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_DECAY_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_DECAY_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_DECAY_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_DECAY_H
 
 #include "src/__support/macros/attributes.h"
 #include "src/__support/macros/config.h"
@@ -35,4 +35,4 @@ template <class T> using decay_t = typename decay<T>::type;
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_DECAY_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_DECAY_H
diff --git a/libc/src/__support/CPP/type_traits/enable_if.h b/libc/src/__support/CPP/type_traits/enable_if.h
index a29fc817bb6c9..1a83c2ca732f9 100644
--- a/libc/src/__support/CPP/type_traits/enable_if.h
+++ b/libc/src/__support/CPP/type_traits/enable_if.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_ENABLE_IF_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_ENABLE_IF_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_ENABLE_IF_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_ENABLE_IF_H
 
 #include "src/__support/CPP/type_traits/type_identity.h"
 
@@ -20,4 +20,4 @@ using enable_if_t = typename enable_if<B, T>::type;
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_ENABLE_IF_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_ENABLE_IF_H
diff --git a/libc/src/__support/CPP/type_traits/false_type.h b/libc/src/__support/CPP/type_traits/false_type.h
index 8dc6fc66d2887..98c6d1c8412ac 100644
--- a/libc/src/__support/CPP/type_traits/false_type.h
+++ b/libc/src/__support/CPP/type_traits/false_type.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_FALSE_TYPE_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_FALSE_TYPE_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_FALSE_TYPE_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_FALSE_TYPE_H
 
 #include "src/__support/CPP/type_traits/bool_constant.h"
 
@@ -17,4 +17,4 @@ using false_type = cpp::bool_constant<false>;
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_FALSE_TYPE_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_FALSE_TYPE_H
diff --git a/libc/src/__support/CPP/type_traits/integral_constant.h b/libc/src/__support/CPP/type_traits/integral_constant.h
index 21bdbccf073a6..958910ca9c5e6 100644
--- a/libc/src/__support/CPP/type_traits/integral_constant.h
+++ b/libc/src/__support/CPP/type_traits/integral_constant.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_INTEGRAL_CONSTANT_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_INTEGRAL_CONSTANT_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_INTEGRAL_CONSTANT_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_INTEGRAL_CONSTANT_H
 
 #include "src/__support/macros/attributes.h" // LIBC_INLINE_VAR
 
@@ -20,4 +20,4 @@ template <typename T, T v> struct integral_constant {
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_INTEGRAL_CONSTANT_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_INTEGRAL_CONSTANT_H
diff --git a/libc/src/__support/CPP/type_traits/invoke.h b/libc/src/__support/CPP/type_traits/invoke.h
index e5294ffcba74f..348abe92db490 100644
--- a/libc/src/__support/CPP/type_traits/invoke.h
+++ b/libc/src/__support/CPP/type_traits/invoke.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_INVOKE_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_INVOKE_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_INVOKE_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_INVOKE_H
 
 #include "src/__support/CPP/type_traits/always_false.h"
 #include "src/__support/CPP/type_traits/decay.h"
@@ -59,4 +59,4 @@ decltype(auto) invoke(Function &&fun, Args &&...args) {
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_INVOKE_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_INVOKE_H
diff --git a/libc/src/__support/CPP/type_traits/invoke_result.h b/libc/src/__support/CPP/type_traits/invoke_result.h
index 20ebba4e4cf95..edcefd28e47e2 100644
--- a/libc/src/__support/CPP/type_traits/invoke_result.h
+++ b/libc/src/__support/CPP/type_traits/invoke_result.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_INVOKE_RESULT_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_INVOKE_RESULT_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_INVOKE_RESULT_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_INVOKE_RESULT_H
 
 #include "src/__support/CPP/type_traits/invoke.h"
 #include "src/__support/CPP/type_traits/type_identity.h"
@@ -23,4 +23,4 @@ using invoke_result_t = typename invoke_result<F, Args...>::type;
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_INVOKE_RESULT_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_INVOKE_RESULT_H
diff --git a/libc/src/__support/CPP/type_traits/is_arithmetic.h b/libc/src/__support/CPP/type_traits/is_arithmetic.h
index cc651b11b2048..9317874b36abf 100644
--- a/libc/src/__support/CPP/type_traits/is_arithmetic.h
+++ b/libc/src/__support/CPP/type_traits/is_arithmetic.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_ARITHMETIC_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_ARITHMETIC_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_ARITHMETIC_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_ARITHMETIC_H
 
 #include "src/__support/CPP/type_traits/bool_constant.h"
 #include "src/__support/CPP/type_traits/is_floating_point.h"
@@ -24,4 +24,4 @@ LIBC_INLINE_VAR constexpr bool is_arithmetic_v = is_arithmetic<T>::value;
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_ARITHMETIC_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_ARITHMETIC_H
diff --git a/libc/src/__support/CPP/type_traits/is_array.h b/libc/src/__support/CPP/type_traits/is_array.h
index c04a2edb6c77e..2d66ff11f707c 100644
--- a/libc/src/__support/CPP/type_traits/is_array.h
+++ b/libc/src/__support/CPP/type_traits/is_array.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_ARRAY_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_ARRAY_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_ARRAY_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_ARRAY_H
 
 #include "src/__support/CPP/type_traits/false_type.h"
 #include "src/__support/CPP/type_traits/true_type.h"
@@ -25,4 +25,4 @@ LIBC_INLINE_VAR constexpr bool is_array_v = is_array<T>::value;
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_ARRAY_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_ARRAY_H
diff --git a/libc/src/__support/CPP/type_traits/is_base_of.h b/libc/src/__support/CPP/type_traits/is_base_of.h
index 7820c83f7cbca..46435f2c7612c 100644
--- a/libc/src/__support/CPP/type_traits/is_base_of.h
+++ b/libc/src/__support/CPP/type_traits/is_base_of.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_BASE_OF_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_BASE_OF_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_BASE_OF_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_BASE_OF_H
 
 #include "src/__support/CPP/type_traits/add_rvalue_reference.h"
 #include "src/__support/CPP/type_traits/false_type.h"
@@ -41,4 +41,4 @@ LIBC_INLINE_VAR constexpr bool is_base_of_v = is_base_of<Base, Derived>::value;
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_BASE_OF_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_BASE_OF_H
diff --git a/libc/src/__support/CPP/type_traits/is_class.h b/libc/src/__support/CPP/type_traits/is_class.h
index 93b3c3d5df33e..bf9c5469f0420 100644
--- a/libc/src/__support/CPP/type_traits/is_class.h
+++ b/libc/src/__support/CPP/type_traits/is_class.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_CLASS_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_CLASS_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_CLASS_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_CLASS_H
 
 #include "src/__support/CPP/type_traits/bool_constant.h"
 #include "src/__support/CPP/type_traits/false_type.h"
@@ -26,4 +26,4 @@ LIBC_INLINE_VAR constexpr bool is_class_v = is_class<T>::value;
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_CLASS_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_CLASS_H
diff --git a/libc/src/__support/CPP/type_traits/is_const.h b/libc/src/__support/CPP/type_traits/is_const.h
index 5434e2982d95c..83e7b83f60f3d 100644
--- a/libc/src/__support/CPP/type_traits/is_const.h
+++ b/libc/src/__support/CPP/type_traits/is_const.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_CONST_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_CONST_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_CONST_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_CONST_H
 
 #include "src/__support/CPP/type_traits/false_type.h"
 #include "src/__support/CPP/type_traits/true_type.h"
@@ -22,4 +22,4 @@ LIBC_INLINE_VAR constexpr bool is_const_v = is_const<T>::value;
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_CONST_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_CONST_H
diff --git a/libc/src/__support/CPP/type_traits/is_convertible.h b/libc/src/__support/CPP/type_traits/is_convertible.h
index a7292c3461d48..cfc82ca716802 100644
--- a/libc/src/__support/CPP/type_traits/is_convertible.h
+++ b/libc/src/__support/CPP/type_traits/is_convertible.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_CONVERTIBLE_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_CONVERTIBLE_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_CONVERTIBLE_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_CONVERTIBLE_H
 
 #include "src/__support/CPP/type_traits/is_void.h"
 #include "src/__support/CPP/utility/declval.h"
@@ -42,4 +42,4 @@ LIBC_INLINE_VAR constexpr bool is_convertible_v =
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_CONVERTIBLE_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_CONVERTIBLE_H
diff --git a/libc/src/__support/CPP/type_traits/is_destructible.h b/libc/src/__support/CPP/type_traits/is_destructible.h
index e466b1c63edcc..2d69fa95a07da 100644
--- a/libc/src/__support/CPP/type_traits/is_destructible.h
+++ b/libc/src/__support/CPP/type_traits/is_destructible.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_DESTRUCTIBLE_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_DESTRUCTIBLE_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_DESTRUCTIBLE_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_DESTRUCTIBLE_H
 
 #include "src/__support/CPP/type_traits/bool_constant.h"
 #include "src/__support/CPP/type_traits/false_type.h"
@@ -63,4 +63,4 @@ LIBC_INLINE_VAR constexpr bool is_destructible_v = is_destructible<T>::value;
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_DESTRUCTIBLE_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_DESTRUCTIBLE_H
diff --git a/libc/src/__support/CPP/type_traits/is_enum.h b/libc/src/__support/CPP/type_traits/is_enum.h
index 4914df30c3cd1..14cea71e0fe4f 100644
--- a/libc/src/__support/CPP/type_traits/is_enum.h
+++ b/libc/src/__support/CPP/type_traits/is_enum.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_ENUM_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_ENUM_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_ENUM_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_ENUM_H
 
 #include "src/__support/CPP/type_traits/bool_constant.h"
 #include "src/__support/macros/attributes.h"
@@ -20,4 +20,4 @@ LIBC_INLINE_VAR constexpr bool is_enum_v = is_enum<T>::value;
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_ENUM_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_ENUM_H
diff --git a/libc/src/__support/CPP/type_traits/is_floating_point.h b/libc/src/__support/CPP/type_traits/is_floating_point.h
index 746d0e36c92eb..ccb004d4cf158 100644
--- a/libc/src/__support/CPP/type_traits/is_floating_point.h
+++ b/libc/src/__support/CPP/type_traits/is_floating_point.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_FLOATING_POINT_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_FLOATING_POINT_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_FLOATING_POINT_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_FLOATING_POINT_H
 
 #include "src/__support/CPP/type_traits/is_same.h"
 #include "src/__support/CPP/type_traits/remove_cv.h"
@@ -32,4 +32,4 @@ LIBC_INLINE_VAR constexpr bool is_floating_point_v =
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_FLOATING_POINT_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_FLOATING_POINT_H
diff --git a/libc/src/__support/CPP/type_traits/is_function.h b/libc/src/__support/CPP/type_traits/is_function.h
index 3a8b3486e8f3a..d8a9166ee99c4 100644
--- a/libc/src/__support/CPP/type_traits/is_function.h
+++ b/libc/src/__support/CPP/type_traits/is_function.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_FUNCTION_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_FUNCTION_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_FUNCTION_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_FUNCTION_H
 
 #include "src/__support/CPP/type_traits/bool_constant.h"
 #include "src/__support/CPP/type_traits/is_const.h"
@@ -30,4 +30,4 @@ LIBC_INLINE_VAR constexpr bool is_function_v = is_function<T>::value;
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_FUNCTION_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_FUNCTION_H
diff --git a/libc/src/__support/CPP/type_traits/is_integral.h b/libc/src/__support/CPP/type_traits/is_integral.h
index 0113a5bf91139..511101c278a94 100644
--- a/libc/src/__support/CPP/type_traits/is_integral.h
+++ b/libc/src/__support/CPP/type_traits/is_integral.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_INTEGRAL_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_INTEGRAL_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_INTEGRAL_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_INTEGRAL_H
 
 #include "src/__support/CPP/type_traits/is_same.h"
 #include "src/__support/CPP/type_traits/remove_cv.h"
@@ -36,4 +36,4 @@ LIBC_INLINE_VAR constexpr bool is_integral_v = is_integral<T>::value;
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_INTEGRAL_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_INTEGRAL_H
diff --git a/libc/src/__support/CPP/type_traits/is_lvalue_reference.h b/libc/src/__support/CPP/type_traits/is_lvalue_reference.h
index fe7f4f7252530..ca3b7d9fc2dd7 100644
--- a/libc/src/__support/CPP/type_traits/is_lvalue_reference.h
+++ b/libc/src/__support/CPP/type_traits/is_lvalue_reference.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_LVALUE_REFERENCE_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_LVALUE_REFERENCE_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_LVALUE_REFERENCE_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_LVALUE_REFERENCE_H
 
 #include "src/__support/CPP/type_traits/bool_constant.h"
 #include "src/__support/CPP/type_traits/false_type.h"
@@ -30,4 +30,4 @@ LIBC_INLINE_VAR constexpr bool is_lvalue_reference_v =
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_LVALUE_REFERENCE_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_LVALUE_REFERENCE_H
diff --git a/libc/src/__support/CPP/type_traits/is_member_pointer.h b/libc/src/__support/CPP/type_traits/is_member_pointer.h
index 5b273d5dc7bde..c885e773de84e 100644
--- a/libc/src/__support/CPP/type_traits/is_member_pointer.h
+++ b/libc/src/__support/CPP/type_traits/is_member_pointer.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_MEMBER_POINTER_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_MEMBER_POINTER_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_MEMBER_POINTER_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_MEMBER_POINTER_H
 
 #include "src/__support/CPP/type_traits/false_type.h"
 #include "src/__support/CPP/type_traits/remove_cv.h"
@@ -27,4 +27,4 @@ LIBC_INLINE_VAR constexpr bool is_member_pointer_v =
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_MEMBER_POINTER_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_MEMBER_POINTER_H
diff --git a/libc/src/__support/CPP/type_traits/is_null_pointer.h b/libc/src/__support/CPP/type_traits/is_null_pointer.h
index 718bd0940f617..bc661e32075ab 100644
--- a/libc/src/__support/CPP/type_traits/is_null_pointer.h
+++ b/libc/src/__support/CPP/type_traits/is_null_pointer.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_NULL_POINTER_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_NULL_POINTER_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_NULL_POINTER_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_NULL_POINTER_H
 
 #include "src/__support/CPP/type_traits/is_same.h"
 #include "src/__support/CPP/type_traits/remove_cv.h"
@@ -23,4 +23,4 @@ LIBC_INLINE_VAR constexpr bool is_null_pointer_v = is_null_pointer<T>::value;
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_NULL_POINTER_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_NULL_POINTER_H
diff --git a/libc/src/__support/CPP/type_traits/is_object.h b/libc/src/__support/CPP/type_traits/is_object.h
index 9928fb7b85e3d..a9dafee7b49a7 100644
--- a/libc/src/__support/CPP/type_traits/is_object.h
+++ b/libc/src/__support/CPP/type_traits/is_object.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_OBJECT_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_OBJECT_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_OBJECT_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_OBJECT_H
 
 #include "src/__support/CPP/type_traits/bool_constant.h"
 #include "src/__support/CPP/type_traits/is_array.h"
@@ -27,4 +27,4 @@ LIBC_INLINE_VAR constexpr bool is_object_v = is_object<T>::value;
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_OBJECT_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_OBJECT_H
diff --git a/libc/src/__support/CPP/type_traits/is_pointer.h b/libc/src/__support/CPP/type_traits/is_pointer.h
index f7af8752e8d89..0903c586c806d 100644
--- a/libc/src/__support/CPP/type_traits/is_pointer.h
+++ b/libc/src/__support/CPP/type_traits/is_pointer.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_POINTER_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_POINTER_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_POINTER_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_POINTER_H
 
 #include "src/__support/CPP/type_traits/false_type.h"
 #include "src/__support/CPP/type_traits/true_type.h"
@@ -25,4 +25,4 @@ LIBC_INLINE_VAR constexpr bool is_pointer_v = is_pointer<T>::value;
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_POINTER_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_POINTER_H
diff --git a/libc/src/__support/CPP/type_traits/is_reference.h b/libc/src/__support/CPP/type_traits/is_reference.h
index 05028a259deb4..ff3b26c769aa1 100644
--- a/libc/src/__support/CPP/type_traits/is_reference.h
+++ b/libc/src/__support/CPP/type_traits/is_reference.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_REFERENCE_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_REFERENCE_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_REFERENCE_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_REFERENCE_H
 
 #include "src/__support/CPP/type_traits/bool_constant.h"
 #include "src/__support/CPP/type_traits/false_type.h"
@@ -29,4 +29,4 @@ LIBC_INLINE_VAR constexpr bool is_reference_v = is_reference<T>::value;
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_REFERENCE_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_REFERENCE_H
diff --git a/libc/src/__support/CPP/type_traits/is_rvalue_reference.h b/libc/src/__support/CPP/type_traits/is_rvalue_reference.h
index 9542454066d94..eb8412a1d82ea 100644
--- a/libc/src/__support/CPP/type_traits/is_rvalue_reference.h
+++ b/libc/src/__support/CPP/type_traits/is_rvalue_reference.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_RVALUE_REFERENCE_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_RVALUE_REFERENCE_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_RVALUE_REFERENCE_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_RVALUE_REFERENCE_H
 
 #include "src/__support/CPP/type_traits/bool_constant.h"
 #include "src/__support/CPP/type_traits/false_type.h"
@@ -30,4 +30,4 @@ LIBC_INLINE_VAR constexpr bool is_rvalue_reference_v =
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_RVALUE_REFERENCE_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_RVALUE_REFERENCE_H
diff --git a/libc/src/__support/CPP/type_traits/is_same.h b/libc/src/__support/CPP/type_traits/is_same.h
index f8fa7ed2f350c..bd1c7362b64cd 100644
--- a/libc/src/__support/CPP/type_traits/is_same.h
+++ b/libc/src/__support/CPP/type_traits/is_same.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_SAME_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_SAME_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_SAME_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_SAME_H
 
 #include "src/__support/CPP/type_traits/false_type.h"
 #include "src/__support/CPP/type_traits/true_type.h"
@@ -22,4 +22,4 @@ LIBC_INLINE_VAR constexpr bool is_same_v = is_same<T, U>::value;
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_SAME_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_SAME_H
diff --git a/libc/src/__support/CPP/type_traits/is_scalar.h b/libc/src/__support/CPP/type_traits/is_scalar.h
index 996fdda2841ab..ed7e34e508d03 100644
--- a/libc/src/__support/CPP/type_traits/is_scalar.h
+++ b/libc/src/__support/CPP/type_traits/is_scalar.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_SCALAR_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_SCALAR_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_SCALAR_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_SCALAR_H
 
 #include "src/__support/CPP/type_traits/bool_constant.h"
 #include "src/__support/CPP/type_traits/is_arithmetic.h"
@@ -29,4 +29,4 @@ LIBC_INLINE_VAR constexpr bool is_scalar_v = is_scalar<T>::value;
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_SCALAR_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_SCALAR_H
diff --git a/libc/src/__support/CPP/type_traits/is_signed.h b/libc/src/__support/CPP/type_traits/is_signed.h
index a4e6dbcf3d62e..71151307129bf 100644
--- a/libc/src/__support/CPP/type_traits/is_signed.h
+++ b/libc/src/__support/CPP/type_traits/is_signed.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_SIGNED_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_SIGNED_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_SIGNED_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_SIGNED_H
 
 #include "src/__support/CPP/type_traits/bool_constant.h"
 #include "src/__support/CPP/type_traits/is_arithmetic.h"
@@ -25,4 +25,4 @@ LIBC_INLINE_VAR constexpr bool is_signed_v = is_signed<T>::value;
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_SIGNED_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_SIGNED_H
diff --git a/libc/src/__support/CPP/type_traits/is_trivially_constructible.h b/libc/src/__support/CPP/type_traits/is_trivially_constructible.h
index 3053e7b9ac53b..daa9c7add2c0a 100644
--- a/libc/src/__support/CPP/type_traits/is_trivially_constructible.h
+++ b/libc/src/__support/CPP/type_traits/is_trivially_constructible.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_TRIVIALLY_CONSTRUCTIBLE_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_TRIVIALLY_CONSTRUCTIBLE_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_TRIVIALLY_CONSTRUCTIBLE_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_TRIVIALLY_CONSTRUCTIBLE_H
 
 #include "src/__support/CPP/type_traits/integral_constant.h"
 
@@ -19,4 +19,4 @@ struct is_trivially_constructible
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_TRIVIALLY_CONSTRUCTIBLE_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_TRIVIALLY_CONSTRUCTIBLE_H
diff --git a/libc/src/__support/CPP/type_traits/is_trivially_copyable.h b/libc/src/__support/CPP/type_traits/is_trivially_copyable.h
index a1b5a0cb26c5f..9e7d05e2ecc74 100644
--- a/libc/src/__support/CPP/type_traits/is_trivially_copyable.h
+++ b/libc/src/__support/CPP/type_traits/is_trivially_copyable.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_TRIVIALLY_COPYABLE_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_TRIVIALLY_COPYABLE_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_TRIVIALLY_COPYABLE_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_TRIVIALLY_COPYABLE_H
 
 #include "src/__support/CPP/type_traits/integral_constant.h"
 #include "src/__support/macros/config.h"
@@ -20,4 +20,4 @@ struct is_trivially_copyable
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_TRIVIALLY_COPYABLE_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_TRIVIALLY_COPYABLE_H
diff --git a/libc/src/__support/CPP/type_traits/is_trivially_destructible.h b/libc/src/__support/CPP/type_traits/is_trivially_destructible.h
index 5eab5aa084604..ce32309b3bf7a 100644
--- a/libc/src/__support/CPP/type_traits/is_trivially_destructible.h
+++ b/libc/src/__support/CPP/type_traits/is_trivially_destructible.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_TRIVIALLY_DESTRUCTIBLE_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_TRIVIALLY_DESTRUCTIBLE_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_TRIVIALLY_DESTRUCTIBLE_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_TRIVIALLY_DESTRUCTIBLE_H
 
 #include "src/__support/CPP/type_traits/bool_constant.h"
 #include "src/__support/CPP/type_traits/is_destructible.h"
@@ -32,4 +32,4 @@ LIBC_INLINE_VAR constexpr bool is_trivially_destructible_v =
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_TRIVIALLY_DESTRUCTIBLE_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_TRIVIALLY_DESTRUCTIBLE_H
diff --git a/libc/src/__support/CPP/type_traits/is_union.h b/libc/src/__support/CPP/type_traits/is_union.h
index 354dbd160844b..807d8f13c2b1c 100644
--- a/libc/src/__support/CPP/type_traits/is_union.h
+++ b/libc/src/__support/CPP/type_traits/is_union.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_UNION_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_UNION_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_UNION_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_UNION_H
 
 #include "src/__support/CPP/type_traits/bool_constant.h"
 #include "src/__support/macros/attributes.h"
@@ -20,4 +20,4 @@ LIBC_INLINE_VAR constexpr bool is_union_v = is_union<T>::value;
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_UNION_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_UNION_H
diff --git a/libc/src/__support/CPP/type_traits/is_unsigned.h b/libc/src/__support/CPP/type_traits/is_unsigned.h
index 6510c1304cf34..c4dc777441e29 100644
--- a/libc/src/__support/CPP/type_traits/is_unsigned.h
+++ b/libc/src/__support/CPP/type_traits/is_unsigned.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_UNSIGNED_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_UNSIGNED_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_UNSIGNED_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_UNSIGNED_H
 
 #include "src/__support/CPP/type_traits/bool_constant.h"
 #include "src/__support/CPP/type_traits/is_arithmetic.h"
@@ -25,4 +25,4 @@ LIBC_INLINE_VAR constexpr bool is_unsigned_v = is_unsigned<T>::value;
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_UNSIGNED_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_UNSIGNED_H
diff --git a/libc/src/__support/CPP/type_traits/is_void.h b/libc/src/__support/CPP/type_traits/is_void.h
index be054f0860c26..54cda12def095 100644
--- a/libc/src/__support/CPP/type_traits/is_void.h
+++ b/libc/src/__support/CPP/type_traits/is_void.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_VOID_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_VOID_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_VOID_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_VOID_H
 
 #include "src/__support/CPP/type_traits/is_same.h"
 #include "src/__support/CPP/type_traits/remove_cv.h"
@@ -21,4 +21,4 @@ LIBC_INLINE_VAR constexpr bool is_void_v = is_void<T>::value;
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_IS_VOID_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_VOID_H
diff --git a/libc/src/__support/CPP/type_traits/make_signed.h b/libc/src/__support/CPP/type_traits/make_signed.h
index c896c45902325..0e8bff68ddb75 100644
--- a/libc/src/__support/CPP/type_traits/make_signed.h
+++ b/libc/src/__support/CPP/type_traits/make_signed.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_MAKE_SIGNED_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_MAKE_SIGNED_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_MAKE_SIGNED_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_MAKE_SIGNED_H
 
 #include "src/__support/CPP/type_traits/type_identity.h"
 
@@ -34,4 +34,4 @@ template <typename T> using make_signed_t = typename make_signed<T>::type;
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_MAKE_SIGNED_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_MAKE_SIGNED_H
diff --git a/libc/src/__support/CPP/type_traits/make_unsigned.h b/libc/src/__support/CPP/type_traits/make_unsigned.h
index 5cd7c3cd4c863..75fc8188b870b 100644
--- a/libc/src/__support/CPP/type_traits/make_unsigned.h
+++ b/libc/src/__support/CPP/type_traits/make_unsigned.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_MAKE_UNSIGNED_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_MAKE_UNSIGNED_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_MAKE_UNSIGNED_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_MAKE_UNSIGNED_H
 
 #include "src/__support/CPP/type_traits/type_identity.h"
 
@@ -39,4 +39,4 @@ template <typename T> using make_unsigned_t = typename make_unsigned<T>::type;
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_MAKE_UNSIGNED_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_MAKE_UNSIGNED_H
diff --git a/libc/src/__support/CPP/type_traits/remove_all_extents.h b/libc/src/__support/CPP/type_traits/remove_all_extents.h
index 54b36a4c2e546..da66043c58c12 100644
--- a/libc/src/__support/CPP/type_traits/remove_all_extents.h
+++ b/libc/src/__support/CPP/type_traits/remove_all_extents.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_REMOVE_ALL_EXTENTS_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_REMOVE_ALL_EXTENTS_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_REMOVE_ALL_EXTENTS_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_REMOVE_ALL_EXTENTS_H
 
 #include "src/__support/CPP/type_traits/type_identity.h"
 #include "src/__support/macros/config.h"
@@ -36,4 +36,4 @@ using remove_all_extents_t = typename remove_all_extents<T>::type;
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_REMOVE_ALL_EXTENTS_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_REMOVE_ALL_EXTENTS_H
diff --git a/libc/src/__support/CPP/type_traits/remove_cv.h b/libc/src/__support/CPP/type_traits/remove_cv.h
index 8ce41d64de277..972e0fc2fdb01 100644
--- a/libc/src/__support/CPP/type_traits/remove_cv.h
+++ b/libc/src/__support/CPP/type_traits/remove_cv.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_REMOVE_CV_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_REMOVE_CV_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_REMOVE_CV_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_REMOVE_CV_H
 
 #include "src/__support/CPP/type_traits/type_identity.h"
 
@@ -22,4 +22,4 @@ template <class T> using remove_cv_t = typename remove_cv<T>::type;
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_REMOVE_CV_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_REMOVE_CV_H
diff --git a/libc/src/__support/CPP/type_traits/remove_cvref.h b/libc/src/__support/CPP/type_traits/remove_cvref.h
index 68eb479f548d4..73831486d0116 100644
--- a/libc/src/__support/CPP/type_traits/remove_cvref.h
+++ b/libc/src/__support/CPP/type_traits/remove_cvref.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_REMOVE_CVREF_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_REMOVE_CVREF_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_REMOVE_CVREF_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_REMOVE_CVREF_H
 
 #include "src/__support/CPP/type_traits/remove_cv.h"
 #include "src/__support/CPP/type_traits/remove_reference.h"
@@ -21,4 +21,4 @@ template <typename T> using remove_cvref_t = typename remove_cvref<T>::type;
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_REMOVE_CVREF_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_REMOVE_CVREF_H
diff --git a/libc/src/__support/CPP/type_traits/remove_extent.h b/libc/src/__support/CPP/type_traits/remove_extent.h
index e80007618dc32..72d8d984427fb 100644
--- a/libc/src/__support/CPP/type_traits/remove_extent.h
+++ b/libc/src/__support/CPP/type_traits/remove_extent.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_REMOVE_EXTENT_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_REMOVE_EXTENT_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_REMOVE_EXTENT_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_REMOVE_EXTENT_H
 
 #include "src/__support/CPP/type_traits/type_identity.h"
 #include "stddef.h" // size_t
@@ -22,4 +22,4 @@ template <class T> using remove_extent_t = typename remove_extent<T>::type;
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_REMOVE_EXTENT_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_REMOVE_EXTENT_H
diff --git a/libc/src/__support/CPP/type_traits/remove_reference.h b/libc/src/__support/CPP/type_traits/remove_reference.h
index b1cb176792738..34f0ae9ff3e3b 100644
--- a/libc/src/__support/CPP/type_traits/remove_reference.h
+++ b/libc/src/__support/CPP/type_traits/remove_reference.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_REMOVE_REFERENCE_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_REMOVE_REFERENCE_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_REMOVE_REFERENCE_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_REMOVE_REFERENCE_H
 
 #include "src/__support/CPP/type_traits/type_identity.h"
 
@@ -21,4 +21,4 @@ using remove_reference_t = typename remove_reference<T>::type;
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_REMOVE_REFERENCE_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_REMOVE_REFERENCE_H
diff --git a/libc/src/__support/CPP/type_traits/true_type.h b/libc/src/__support/CPP/type_traits/true_type.h
index 41f1fcadf1895..8551cef874f7c 100644
--- a/libc/src/__support/CPP/type_traits/true_type.h
+++ b/libc/src/__support/CPP/type_traits/true_type.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_TRUE_TYPE_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_TRUE_TYPE_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_TRUE_TYPE_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_TRUE_TYPE_H
 
 #include "src/__support/CPP/type_traits/bool_constant.h"
 
@@ -17,4 +17,4 @@ using true_type = cpp::bool_constant<true>;
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_TRUE_TYPE_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_TRUE_TYPE_H
diff --git a/libc/src/__support/CPP/type_traits/type_identity.h b/libc/src/__support/CPP/type_traits/type_identity.h
index eaba0a9fbec47..0804276a5424d 100644
--- a/libc/src/__support/CPP/type_traits/type_identity.h
+++ b/libc/src/__support/CPP/type_traits/type_identity.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_TYPE_IDENTITY_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_TYPE_IDENTITY_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_TYPE_IDENTITY_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_TYPE_IDENTITY_H
 
 namespace __llvm_libc::cpp {
 
@@ -17,4 +17,4 @@ template <typename T> struct type_identity {
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_TYPE_IDENTITY_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_TYPE_IDENTITY_H
diff --git a/libc/src/__support/CPP/type_traits/void_t.h b/libc/src/__support/CPP/type_traits/void_t.h
index 237e7ce974415..03fe6b957e712 100644
--- a/libc/src/__support/CPP/type_traits/void_t.h
+++ b/libc/src/__support/CPP/type_traits/void_t.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_VOID_T_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_VOID_T_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_VOID_T_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_VOID_T_H
 
 #include "src/__support/CPP/type_traits/type_identity.h"
 
@@ -23,4 +23,4 @@ using void_t = typename detail::make_void<Ts...>::type;
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_TYPE_TRAITS_VOID_T_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_VOID_T_H
diff --git a/libc/src/__support/CPP/utility.h b/libc/src/__support/CPP/utility.h
index 9be50350292db..083b4877c3921 100644
--- a/libc/src/__support/CPP/utility.h
+++ b/libc/src/__support/CPP/utility.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_UTILITY_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_UTILITY_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_UTILITY_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_UTILITY_H
 
 #include "src/__support/CPP/utility/declval.h"
 #include "src/__support/CPP/utility/forward.h"
@@ -15,4 +15,4 @@
 #include "src/__support/CPP/utility/integer_sequence.h"
 #include "src/__support/CPP/utility/move.h"
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_UTILITY_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_UTILITY_H
diff --git a/libc/src/__support/CPP/utility/declval.h b/libc/src/__support/CPP/utility/declval.h
index 21bb973de0dd0..2522baf0e1b15 100644
--- a/libc/src/__support/CPP/utility/declval.h
+++ b/libc/src/__support/CPP/utility/declval.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_UTILITY_DECLVAL_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_UTILITY_DECLVAL_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_UTILITY_DECLVAL_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_UTILITY_DECLVAL_H
 
 #include "src/__support/CPP/type_traits/add_rvalue_reference.h"
 #include "src/__support/CPP/type_traits/always_false.h"
@@ -21,4 +21,4 @@ template <typename T> cpp::add_rvalue_reference_t<T> declval() {
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_UTILITY_DECLVAL_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_UTILITY_DECLVAL_H
diff --git a/libc/src/__support/CPP/utility/forward.h b/libc/src/__support/CPP/utility/forward.h
index a6698a589cb40..78ffb736ceb3d 100644
--- a/libc/src/__support/CPP/utility/forward.h
+++ b/libc/src/__support/CPP/utility/forward.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_UTILITY_FORWARD_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_UTILITY_FORWARD_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_UTILITY_FORWARD_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_UTILITY_FORWARD_H
 
 #include "src/__support/CPP/type_traits/is_lvalue_reference.h"
 #include "src/__support/CPP/type_traits/remove_reference.h"
@@ -29,4 +29,4 @@ LIBC_INLINE constexpr T &&forward(remove_reference_t<T> &&value) {
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_UTILITY_FORWARD_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_UTILITY_FORWARD_H
diff --git a/libc/src/__support/CPP/utility/in_place.h b/libc/src/__support/CPP/utility/in_place.h
index 45c37066a4f12..dfb7486c4eba0 100644
--- a/libc/src/__support/CPP/utility/in_place.h
+++ b/libc/src/__support/CPP/utility/in_place.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_UTILITY_IN_PLACE_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_UTILITY_IN_PLACE_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_UTILITY_IN_PLACE_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_UTILITY_IN_PLACE_H
 
 #include "src/__support/macros/attributes.h"
 
@@ -33,4 +33,4 @@ LIBC_INLINE_VAR constexpr in_place_index_t<I> in_place_index{};
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_UTILITY_IN_PLACE_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_UTILITY_IN_PLACE_H
diff --git a/libc/src/__support/CPP/utility/integer_sequence.h b/libc/src/__support/CPP/utility/integer_sequence.h
index 471567f714f88..3d2e001e87799 100644
--- a/libc/src/__support/CPP/utility/integer_sequence.h
+++ b/libc/src/__support/CPP/utility/integer_sequence.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_UTILITY_INTEGER_SEQUENCE_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_UTILITY_INTEGER_SEQUENCE_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_UTILITY_INTEGER_SEQUENCE_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_UTILITY_INTEGER_SEQUENCE_H
 
 #include "src/__support/CPP/type_traits/is_integral.h"
 
@@ -34,4 +34,4 @@ using make_integer_sequence =
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_UTILITY_INTEGER_SEQUENCE_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_UTILITY_INTEGER_SEQUENCE_H
diff --git a/libc/src/__support/CPP/utility/move.h b/libc/src/__support/CPP/utility/move.h
index 3cc73c76ce9af..bc0b63e3687c8 100644
--- a/libc/src/__support/CPP/utility/move.h
+++ b/libc/src/__support/CPP/utility/move.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LLVM_LIBC_SRC_SUPPORT_CPP_UTILITY_MOVE_H
-#define LLVM_LIBC_SRC_SUPPORT_CPP_UTILITY_MOVE_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CPP_UTILITY_MOVE_H
+#define LLVM_LIBC_SRC___SUPPORT_CPP_UTILITY_MOVE_H
 
 #include "src/__support/CPP/type_traits/remove_reference.h"
 
@@ -19,4 +19,4 @@ template <class T> constexpr cpp::remove_reference_t<T> &&move(T &&t) {
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CPP_UTILITY_MOVE_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CPP_UTILITY_MOVE_H
diff --git a/libc/src/__support/FPUtil/BasicOperations.h b/libc/src/__support/FPUtil/BasicOperations.h
index 7f735656736ac..67b8e666479f2 100644
--- a/libc/src/__support/FPUtil/BasicOperations.h
+++ b/libc/src/__support/FPUtil/BasicOperations.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_FPUTIL_BASIC_OPERATIONS_H
-#define LLVM_LIBC_SRC_SUPPORT_FPUTIL_BASIC_OPERATIONS_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_FPUTIL_BASICOPERATIONS_H
+#define LLVM_LIBC_SRC___SUPPORT_FPUTIL_BASICOPERATIONS_H
 
 #include "FPBits.h"
 
@@ -78,4 +78,4 @@ LIBC_INLINE T fdim(T x, T y) {
 } // namespace fputil
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_FPUTIL_BASIC_OPERATIONS_H
+#endif // LLVM_LIBC_SRC___SUPPORT_FPUTIL_BASICOPERATIONS_H
diff --git a/libc/src/__support/FPUtil/DivisionAndRemainderOperations.h b/libc/src/__support/FPUtil/DivisionAndRemainderOperations.h
index 7b9d7fa49d7ac..f0b5ba98e43ab 100644
--- a/libc/src/__support/FPUtil/DivisionAndRemainderOperations.h
+++ b/libc/src/__support/FPUtil/DivisionAndRemainderOperations.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_FPUTIL_DIVISION_AND_REMAINDER_OPERATIONS_H
-#define LLVM_LIBC_SRC_SUPPORT_FPUTIL_DIVISION_AND_REMAINDER_OPERATIONS_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_FPUTIL_DIVISIONANDREMAINDEROPERATIONS_H
+#define LLVM_LIBC_SRC___SUPPORT_FPUTIL_DIVISIONANDREMAINDEROPERATIONS_H
 
 #include "FPBits.h"
 #include "ManipulationFunctions.h"
@@ -116,4 +116,4 @@ LIBC_INLINE T remquo(T x, T y, int &q) {
 } // namespace fputil
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_FPUTIL_DIVISION_AND_REMAINDER_OPERATIONS_H
+#endif // LLVM_LIBC_SRC___SUPPORT_FPUTIL_DIVISIONANDREMAINDEROPERATIONS_H
diff --git a/libc/src/__support/FPUtil/FEnvImpl.h b/libc/src/__support/FPUtil/FEnvImpl.h
index f525004c294c3..29ae4a37f8823 100644
--- a/libc/src/__support/FPUtil/FEnvImpl.h
+++ b/libc/src/__support/FPUtil/FEnvImpl.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_FPUTIL_FENVIMPL_H
-#define LLVM_LIBC_SRC_SUPPORT_FPUTIL_FENVIMPL_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_FPUTIL_FENVIMPL_H
+#define LLVM_LIBC_SRC___SUPPORT_FPUTIL_FENVIMPL_H
 
 #include "src/__support/macros/attributes.h" // LIBC_INLINE
 #include "src/__support/macros/properties/architectures.h"
@@ -88,4 +88,4 @@ LIBC_INLINE void set_errno_if_required(int err) {
 
 } // namespace __llvm_libc::fputil
 
-#endif // LLVM_LIBC_SRC_SUPPORT_FPUTIL_FENVIMPL_H
+#endif // LLVM_LIBC_SRC___SUPPORT_FPUTIL_FENVIMPL_H
diff --git a/libc/src/__support/FPUtil/FMA.h b/libc/src/__support/FPUtil/FMA.h
index 178d34fd73f14..eb95bf0f2ee10 100644
--- a/libc/src/__support/FPUtil/FMA.h
+++ b/libc/src/__support/FPUtil/FMA.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_FPUTIL_FMA_H
-#define LLVM_LIBC_SRC_SUPPORT_FPUTIL_FMA_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_FPUTIL_FMA_H
+#define LLVM_LIBC_SRC___SUPPORT_FPUTIL_FMA_H
 
 #include "src/__support/macros/properties/architectures.h"
 #include "src/__support/macros/properties/cpu_features.h" // LIBC_TARGET_CPU_HAS_FMA
@@ -41,4 +41,4 @@ template <typename T> LIBC_INLINE T fma(T x, T y, T z) {
 
 #endif
 
-#endif // LLVM_LIBC_SRC_SUPPORT_FPUTIL_FMA_H
+#endif // LLVM_LIBC_SRC___SUPPORT_FPUTIL_FMA_H
diff --git a/libc/src/__support/FPUtil/FPBits.h b/libc/src/__support/FPUtil/FPBits.h
index 326211669dce6..d7ab076130840 100644
--- a/libc/src/__support/FPUtil/FPBits.h
+++ b/libc/src/__support/FPUtil/FPBits.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_FPUTIL_FP_BITS_H
-#define LLVM_LIBC_SRC_SUPPORT_FPUTIL_FP_BITS_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_FPUTIL_FPBITS_H
+#define LLVM_LIBC_SRC___SUPPORT_FPUTIL_FPBITS_H
 
 #include "PlatformDefs.h"
 
@@ -239,4 +239,4 @@ template <typename T> struct FPBits {
 #include "x86_64/LongDoubleBits.h"
 #endif
 
-#endif // LLVM_LIBC_SRC_SUPPORT_FPUTIL_FP_BITS_H
+#endif // LLVM_LIBC_SRC___SUPPORT_FPUTIL_FPBITS_H
diff --git a/libc/src/__support/FPUtil/FloatProperties.h b/libc/src/__support/FPUtil/FloatProperties.h
index b463441847a30..3df961a9380e5 100644
--- a/libc/src/__support/FPUtil/FloatProperties.h
+++ b/libc/src/__support/FPUtil/FloatProperties.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_FPUTIL_FLOAT_PROPERTIES_H
-#define LLVM_LIBC_SRC_SUPPORT_FPUTIL_FLOAT_PROPERTIES_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_FPUTIL_FLOATPROPERTIES_H
+#define LLVM_LIBC_SRC___SUPPORT_FPUTIL_FLOATPROPERTIES_H
 
 #include "PlatformDefs.h"
 
@@ -196,4 +196,4 @@ using FloatTypeT = typename FloatType<BitsType>::Type;
 } // namespace fputil
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_FPUTIL_FLOAT_PROPERTIES_H
+#endif // LLVM_LIBC_SRC___SUPPORT_FPUTIL_FLOATPROPERTIES_H
diff --git a/libc/src/__support/FPUtil/Hypot.h b/libc/src/__support/FPUtil/Hypot.h
index 61bf10bfc4f6c..5bf6db72bdc13 100644
--- a/libc/src/__support/FPUtil/Hypot.h
+++ b/libc/src/__support/FPUtil/Hypot.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_FPUTIL_HYPOT_H
-#define LLVM_LIBC_SRC_SUPPORT_FPUTIL_HYPOT_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_FPUTIL_HYPOT_H
+#define LLVM_LIBC_SRC___SUPPORT_FPUTIL_HYPOT_H
 
 #include "BasicOperations.h"
 #include "FEnvImpl.h"
@@ -262,4 +262,4 @@ LIBC_INLINE T hypot(T x, T y) {
 } // namespace fputil
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_FPUTIL_HYPOT_H
+#endif // LLVM_LIBC_SRC___SUPPORT_FPUTIL_HYPOT_H
diff --git a/libc/src/__support/FPUtil/ManipulationFunctions.h b/libc/src/__support/FPUtil/ManipulationFunctions.h
index 14055ab74dce0..676dafa27c963 100644
--- a/libc/src/__support/FPUtil/ManipulationFunctions.h
+++ b/libc/src/__support/FPUtil/ManipulationFunctions.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_FPUTIL_MANIPULATION_FUNCTIONS_H
-#define LLVM_LIBC_SRC_SUPPORT_FPUTIL_MANIPULATION_FUNCTIONS_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_FPUTIL_MANIPULATIONFUNCTIONS_H
+#define LLVM_LIBC_SRC___SUPPORT_FPUTIL_MANIPULATIONFUNCTIONS_H
 
 #include "FPBits.h"
 #include "NearestIntegerOperations.h"
@@ -180,4 +180,4 @@ LIBC_INLINE T nextafter(T from, T to) {
 #include "x86_64/NextAfterLongDouble.h"
 #endif // SPECIAL_X86_LONG_DOUBLE
 
-#endif // LLVM_LIBC_SRC_SUPPORT_FPUTIL_MANIPULATION_FUNCTIONS_H
+#endif // LLVM_LIBC_SRC___SUPPORT_FPUTIL_MANIPULATIONFUNCTIONS_H
diff --git a/libc/src/__support/FPUtil/NearestIntegerOperations.h b/libc/src/__support/FPUtil/NearestIntegerOperations.h
index 96007ac5b7f57..9f151f24f3b8a 100644
--- a/libc/src/__support/FPUtil/NearestIntegerOperations.h
+++ b/libc/src/__support/FPUtil/NearestIntegerOperations.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_FPUTIL_NEAREST_INTEGER_OPERATIONS_H
-#define LLVM_LIBC_SRC_SUPPORT_FPUTIL_NEAREST_INTEGER_OPERATIONS_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_FPUTIL_NEARESTINTEGEROPERATIONS_H
+#define LLVM_LIBC_SRC___SUPPORT_FPUTIL_NEARESTINTEGEROPERATIONS_H
 
 #include "FEnvImpl.h"
 #include "FPBits.h"
@@ -288,4 +288,4 @@ LIBC_INLINE I round_to_signed_integer_using_current_rounding_mode(F x) {
 } // namespace fputil
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_FPUTIL_NEAREST_INTEGER_OPERATIONS_H
+#endif // LLVM_LIBC_SRC___SUPPORT_FPUTIL_NEARESTINTEGEROPERATIONS_H
diff --git a/libc/src/__support/FPUtil/NormalFloat.h b/libc/src/__support/FPUtil/NormalFloat.h
index edeed0c65932c..0b2eb628ee196 100644
--- a/libc/src/__support/FPUtil/NormalFloat.h
+++ b/libc/src/__support/FPUtil/NormalFloat.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_FPUTIL_NORMAL_FLOAT_H
-#define LLVM_LIBC_SRC_SUPPORT_FPUTIL_NORMAL_FLOAT_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_FPUTIL_NORMALFLOAT_H
+#define LLVM_LIBC_SRC___SUPPORT_FPUTIL_NORMALFLOAT_H
 
 #include "FPBits.h"
 
@@ -264,4 +264,4 @@ template <> LIBC_INLINE NormalFloat<long double>::operator long double() const {
 } // namespace fputil
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_FPUTIL_NORMAL_FLOAT_H
+#endif // LLVM_LIBC_SRC___SUPPORT_FPUTIL_NORMALFLOAT_H
diff --git a/libc/src/__support/FPUtil/PlatformDefs.h b/libc/src/__support/FPUtil/PlatformDefs.h
index 175a62a1c930e..7bf6db3a1ef29 100644
--- a/libc/src/__support/FPUtil/PlatformDefs.h
+++ b/libc/src/__support/FPUtil/PlatformDefs.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_FPUTIL_PLATFORM_DEFS_H
-#define LLVM_LIBC_SRC_SUPPORT_FPUTIL_PLATFORM_DEFS_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_FPUTIL_PLATFORMDEFS_H
+#define LLVM_LIBC_SRC___SUPPORT_FPUTIL_PLATFORMDEFS_H
 
 #include "src/__support/macros/properties/architectures.h"
 
@@ -27,4 +27,4 @@
 #define SPECIAL_X86_LONG_DOUBLE
 #endif
 
-#endif // LLVM_LIBC_SRC_SUPPORT_FPUTIL_PLATFORM_DEFS_H
+#endif // LLVM_LIBC_SRC___SUPPORT_FPUTIL_PLATFORMDEFS_H
diff --git a/libc/src/__support/FPUtil/PolyEval.h b/libc/src/__support/FPUtil/PolyEval.h
index 7f4af5c3406c2..12027289bde9e 100644
--- a/libc/src/__support/FPUtil/PolyEval.h
+++ b/libc/src/__support/FPUtil/PolyEval.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_FPUTIL_POLYEVAL_H
-#define LLVM_LIBC_SRC_SUPPORT_FPUTIL_POLYEVAL_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_FPUTIL_POLYEVAL_H
+#define LLVM_LIBC_SRC___SUPPORT_FPUTIL_POLYEVAL_H
 
 #include "multiply_add.h"
 #include "src/__support/CPP/type_traits.h"
@@ -50,4 +50,4 @@ polyeval(T x, T a0, Ts... a) {
 } // namespace fputil
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_FPUTIL_POLYEVAL_H
+#endif // LLVM_LIBC_SRC___SUPPORT_FPUTIL_POLYEVAL_H
diff --git a/libc/src/__support/FPUtil/aarch64/FEnvImpl.h b/libc/src/__support/FPUtil/aarch64/FEnvImpl.h
index 783d3f3f56eb4..4cc4920bb39c1 100644
--- a/libc/src/__support/FPUtil/aarch64/FEnvImpl.h
+++ b/libc/src/__support/FPUtil/aarch64/FEnvImpl.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_FPUTIL_AARCH64_FENVIMPL_H
-#define LLVM_LIBC_SRC_SUPPORT_FPUTIL_AARCH64_FENVIMPL_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_FPUTIL_AARCH64_FENVIMPL_H
+#define LLVM_LIBC_SRC___SUPPORT_FPUTIL_AARCH64_FENVIMPL_H
 
 #include "src/__support/macros/attributes.h" // LIBC_INLINE
 #include "src/__support/macros/properties/architectures.h"
@@ -280,4 +280,4 @@ LIBC_INLINE int set_env(const fenv_t *envp) {
 } // namespace fputil
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_FPUTIL_AARCH64_FENVIMPL_H
+#endif // LLVM_LIBC_SRC___SUPPORT_FPUTIL_AARCH64_FENVIMPL_H
diff --git a/libc/src/__support/FPUtil/aarch64/FMA.h b/libc/src/__support/FPUtil/aarch64/FMA.h
index bcc4c70fc4e0b..eaa3b2c11bb2a 100644
--- a/libc/src/__support/FPUtil/aarch64/FMA.h
+++ b/libc/src/__support/FPUtil/aarch64/FMA.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_FPUTIL_AARCH64_FMA_H
-#define LLVM_LIBC_SRC_SUPPORT_FPUTIL_AARCH64_FMA_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_FPUTIL_AARCH64_FMA_H
+#define LLVM_LIBC_SRC___SUPPORT_FPUTIL_AARCH64_FMA_H
 
 #include "src/__support/macros/attributes.h" // LIBC_INLINE
 #include "src/__support/macros/properties/architectures.h"
@@ -47,4 +47,4 @@ LIBC_INLINE cpp::enable_if_t<cpp::is_same_v<T, double>, T> fma(T x, T y, T z) {
 } // namespace fputil
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_FPUTIL_AARCH64_FMA_H
+#endif // LLVM_LIBC_SRC___SUPPORT_FPUTIL_AARCH64_FMA_H
diff --git a/libc/src/__support/FPUtil/aarch64/fenv_darwin_impl.h b/libc/src/__support/FPUtil/aarch64/fenv_darwin_impl.h
index d9acc717a8bb3..9243df1e36035 100644
--- a/libc/src/__support/FPUtil/aarch64/fenv_darwin_impl.h
+++ b/libc/src/__support/FPUtil/aarch64/fenv_darwin_impl.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_FPUTIL_AARCH64_FENV_DARWIN_IMPL_H
-#define LLVM_LIBC_SRC_SUPPORT_FPUTIL_AARCH64_FENV_DARWIN_IMPL_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_FPUTIL_AARCH64_FENV_DARWIN_IMPL_H
+#define LLVM_LIBC_SRC___SUPPORT_FPUTIL_AARCH64_FENV_DARWIN_IMPL_H
 
 #include "src/__support/macros/attributes.h" // LIBC_INLINE
 #include "src/__support/macros/properties/architectures.h"
@@ -285,4 +285,4 @@ LIBC_INLINE int set_env(const fenv_t *envp) {
 } // namespace fputil
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_FPUTIL_AARCH64_FENV_DARWIN_IMPL_H
+#endif // LLVM_LIBC_SRC___SUPPORT_FPUTIL_AARCH64_FENV_DARWIN_IMPL_H
diff --git a/libc/src/__support/FPUtil/aarch64/nearest_integer.h b/libc/src/__support/FPUtil/aarch64/nearest_integer.h
index 1726ec056ad50..2ee4e3363a11b 100644
--- a/libc/src/__support/FPUtil/aarch64/nearest_integer.h
+++ b/libc/src/__support/FPUtil/aarch64/nearest_integer.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_FPUTIL_AARCH64_NEAREST_INTEGER_H
-#define LLVM_LIBC_SRC_SUPPORT_FPUTIL_AARCH64_NEAREST_INTEGER_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_FPUTIL_AARCH64_NEAREST_INTEGER_H
+#define LLVM_LIBC_SRC___SUPPORT_FPUTIL_AARCH64_NEAREST_INTEGER_H
 
 #include "src/__support/common.h"
 #include "src/__support/macros/properties/architectures.h"
@@ -34,4 +34,4 @@ LIBC_INLINE double nearest_integer(double x) {
 } // namespace fputil
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_FPUTIL_AARCH64_NEAREST_INTEGER_H
+#endif // LLVM_LIBC_SRC___SUPPORT_FPUTIL_AARCH64_NEAREST_INTEGER_H
diff --git a/libc/src/__support/FPUtil/aarch64/sqrt.h b/libc/src/__support/FPUtil/aarch64/sqrt.h
index f98e4a8f6e006..6edf2a489064f 100644
--- a/libc/src/__support/FPUtil/aarch64/sqrt.h
+++ b/libc/src/__support/FPUtil/aarch64/sqrt.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_FPUTIL_AARCH64_SQRT_H
-#define LLVM_LIBC_SRC_SUPPORT_FPUTIL_AARCH64_SQRT_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_FPUTIL_AARCH64_SQRT_H
+#define LLVM_LIBC_SRC___SUPPORT_FPUTIL_AARCH64_SQRT_H
 
 #include "src/__support/common.h"
 #include "src/__support/macros/properties/architectures.h"
@@ -36,4 +36,4 @@ template <> LIBC_INLINE double sqrt<double>(double x) {
 } // namespace fputil
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_FPUTIL_AARCH64_SQRT_H
+#endif // LLVM_LIBC_SRC___SUPPORT_FPUTIL_AARCH64_SQRT_H
diff --git a/libc/src/__support/FPUtil/arm/FEnvImpl.h b/libc/src/__support/FPUtil/arm/FEnvImpl.h
index 02535ecbca199..5e856075b1d76 100644
--- a/libc/src/__support/FPUtil/arm/FEnvImpl.h
+++ b/libc/src/__support/FPUtil/arm/FEnvImpl.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_FPUTIL_ARM_FENVIMPL_H
-#define LLVM_LIBC_SRC_SUPPORT_FPUTIL_ARM_FENVIMPL_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_FPUTIL_ARM_FENVIMPL_H
+#define LLVM_LIBC_SRC___SUPPORT_FPUTIL_ARM_FENVIMPL_H
 
 #include "src/__support/FPUtil/FPBits.h"
 #include "src/__support/macros/config.h" // For LIBC_INLINE
@@ -262,4 +262,4 @@ LIBC_INLINE int set_env(const fenv_t *envp) {
 } // namespace fputil
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_FPUTIL_ARM_FENVIMPL_H
+#endif // LLVM_LIBC_SRC___SUPPORT_FPUTIL_ARM_FENVIMPL_H
diff --git a/libc/src/__support/FPUtil/double_double.h b/libc/src/__support/FPUtil/double_double.h
index 9048fed241964..fd44d5e95268f 100644
--- a/libc/src/__support/FPUtil/double_double.h
+++ b/libc/src/__support/FPUtil/double_double.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_FPUTIL_DOUBLEDOUBLE_H
-#define LLVM_LIBC_SRC_SUPPORT_FPUTIL_DOUBLEDOUBLE_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_FPUTIL_DOUBLE_DOUBLE_H
+#define LLVM_LIBC_SRC___SUPPORT_FPUTIL_DOUBLE_DOUBLE_H
 
 #include "multiply_add.h"
 #include "src/__support/common.h"
@@ -101,4 +101,4 @@ LIBC_INLINE DoubleDouble multiply_add<DoubleDouble>(const DoubleDouble &a,
 
 } // namespace __llvm_libc::fputil
 
-#endif // LLVM_LIBC_SRC_SUPPORT_FPUTIL_DOUBLEDOUBLE_H
+#endif // LLVM_LIBC_SRC___SUPPORT_FPUTIL_DOUBLE_DOUBLE_H
diff --git a/libc/src/__support/FPUtil/dyadic_float.h b/libc/src/__support/FPUtil/dyadic_float.h
index 449e2de267966..ec000d592b9fe 100644
--- a/libc/src/__support/FPUtil/dyadic_float.h
+++ b/libc/src/__support/FPUtil/dyadic_float.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_FPUTIL_DYADIC_FLOAT_H
-#define LLVM_LIBC_SRC_SUPPORT_FPUTIL_DYADIC_FLOAT_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_FPUTIL_DYADIC_FLOAT_H
+#define LLVM_LIBC_SRC___SUPPORT_FPUTIL_DYADIC_FLOAT_H
 
 #include "FPBits.h"
 #include "FloatProperties.h"
@@ -308,4 +308,4 @@ constexpr DyadicFloat<Bits> mul_pow_2(DyadicFloat<Bits> a, int32_t pow_2) {
 
 } // namespace __llvm_libc::fputil
 
-#endif // LLVM_LIBC_SRC_SUPPORT_FPUTIL_DYADIC_FLOAT_H
+#endif // LLVM_LIBC_SRC___SUPPORT_FPUTIL_DYADIC_FLOAT_H
diff --git a/libc/src/__support/FPUtil/except_value_utils.h b/libc/src/__support/FPUtil/except_value_utils.h
index df1b9c74aab28..0229c961f0536 100644
--- a/libc/src/__support/FPUtil/except_value_utils.h
+++ b/libc/src/__support/FPUtil/except_value_utils.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_FPUTIL_EXCEPT_VALUE_UTILS_H
-#define LLVM_LIBC_SRC_SUPPORT_FPUTIL_EXCEPT_VALUE_UTILS_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_FPUTIL_EXCEPT_VALUE_UTILS_H
+#define LLVM_LIBC_SRC___SUPPORT_FPUTIL_EXCEPT_VALUE_UTILS_H
 
 #include "FEnvImpl.h"
 #include "FPBits.h"
@@ -116,4 +116,4 @@ LIBC_INLINE float round_result_slightly_up(float value_rn) {
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_FPUTIL_EXCEPT_VALUE_UTILS_H
+#endif // LLVM_LIBC_SRC___SUPPORT_FPUTIL_EXCEPT_VALUE_UTILS_H
diff --git a/libc/src/__support/FPUtil/fpbits_str.h b/libc/src/__support/FPUtil/fpbits_str.h
index 0a1041e15221d..46cd102d83f64 100644
--- a/libc/src/__support/FPUtil/fpbits_str.h
+++ b/libc/src/__support/FPUtil/fpbits_str.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_FPUTIL_FP_BITS_STR_H
-#define LLVM_LIBC_SRC_SUPPORT_FPUTIL_FP_BITS_STR_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_FPUTIL_FP_BITS_STR_H
+#define LLVM_LIBC_SRC___SUPPORT_FPUTIL_FP_BITS_STR_H
 
 #include "src/__support/CPP/string.h"
 #include "src/__support/CPP/type_traits.h"
@@ -72,4 +72,4 @@ template <typename T> LIBC_INLINE cpp::string str(fputil::FPBits<T> x) {
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_FPUTIL_FP_BITS_STR_H
+#endif // LLVM_LIBC_SRC___SUPPORT_FPUTIL_FP_BITS_STR_H
diff --git a/libc/src/__support/FPUtil/generic/FMA.h b/libc/src/__support/FPUtil/generic/FMA.h
index 5aba4309af0fb..ee6659346de4e 100644
--- a/libc/src/__support/FPUtil/generic/FMA.h
+++ b/libc/src/__support/FPUtil/generic/FMA.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_FPUTIL_GENERIC_FMA_H
-#define LLVM_LIBC_SRC_SUPPORT_FPUTIL_GENERIC_FMA_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_FPUTIL_GENERIC_FMA_H
+#define LLVM_LIBC_SRC___SUPPORT_FPUTIL_GENERIC_FMA_H
 
 #include "src/__support/CPP/type_traits.h"
 #include "src/__support/FPUtil/FEnvImpl.h"
@@ -292,4 +292,4 @@ template <> LIBC_INLINE double fma<double>(double x, double y, double z) {
 } // namespace fputil
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_FPUTIL_GENERIC_FMA_H
+#endif // LLVM_LIBC_SRC___SUPPORT_FPUTIL_GENERIC_FMA_H
diff --git a/libc/src/__support/FPUtil/generic/FMod.h b/libc/src/__support/FPUtil/generic/FMod.h
index fd40d87132922..10998443d854b 100644
--- a/libc/src/__support/FPUtil/generic/FMod.h
+++ b/libc/src/__support/FPUtil/generic/FMod.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_FPUTIL_GENERIC_FMOD_H
-#define LLVM_LIBC_SRC_SUPPORT_FPUTIL_GENERIC_FMOD_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_FPUTIL_GENERIC_FMOD_H
+#define LLVM_LIBC_SRC___SUPPORT_FPUTIL_GENERIC_FMOD_H
 
 #include "src/__support/CPP/limits.h"
 #include "src/__support/CPP/type_traits.h"
@@ -319,4 +319,4 @@ class FMod {
 } // namespace fputil
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_FPUTIL_GENERIC_FMOD_H
+#endif // LLVM_LIBC_SRC___SUPPORT_FPUTIL_GENERIC_FMOD_H
diff --git a/libc/src/__support/FPUtil/generic/sqrt.h b/libc/src/__support/FPUtil/generic/sqrt.h
index d2697f8869dfe..35ace1365c442 100644
--- a/libc/src/__support/FPUtil/generic/sqrt.h
+++ b/libc/src/__support/FPUtil/generic/sqrt.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_FPUTIL_GENERIC_SQRT_H
-#define LLVM_LIBC_SRC_SUPPORT_FPUTIL_GENERIC_SQRT_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_FPUTIL_GENERIC_SQRT_H
+#define LLVM_LIBC_SRC___SUPPORT_FPUTIL_GENERIC_SQRT_H
 
 #include "sqrt_80_bit_long_double.h"
 #include "src/__support/CPP/bit.h"
@@ -171,4 +171,4 @@ LIBC_INLINE cpp::enable_if_t<cpp::is_floating_point_v<T>, T> sqrt(T x) {
 } // namespace fputil
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_FPUTIL_GENERIC_SQRT_H
+#endif // LLVM_LIBC_SRC___SUPPORT_FPUTIL_GENERIC_SQRT_H
diff --git a/libc/src/__support/FPUtil/generic/sqrt_80_bit_long_double.h b/libc/src/__support/FPUtil/generic/sqrt_80_bit_long_double.h
index a8e818dce990b..2b03273f29c40 100644
--- a/libc/src/__support/FPUtil/generic/sqrt_80_bit_long_double.h
+++ b/libc/src/__support/FPUtil/generic/sqrt_80_bit_long_double.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_FPUTIL_GENERIC_SQRT_80_BIT_LONG_DOUBLE_H
-#define LLVM_LIBC_SRC_SUPPORT_FPUTIL_GENERIC_SQRT_80_BIT_LONG_DOUBLE_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_FPUTIL_GENERIC_SQRT_80_BIT_LONG_DOUBLE_H
+#define LLVM_LIBC_SRC___SUPPORT_FPUTIL_GENERIC_SQRT_80_BIT_LONG_DOUBLE_H
 
 #include "src/__support/FPUtil/FEnvImpl.h"
 #include "src/__support/FPUtil/FPBits.h"
@@ -142,4 +142,4 @@ LIBC_INLINE long double sqrt(long double x) {
 } // namespace fputil
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_FPUTIL_GENERIC_SQRT_80_BIT_LONG_DOUBLE_H
+#endif // LLVM_LIBC_SRC___SUPPORT_FPUTIL_GENERIC_SQRT_80_BIT_LONG_DOUBLE_H
diff --git a/libc/src/__support/FPUtil/gpu/FMA.h b/libc/src/__support/FPUtil/gpu/FMA.h
index 2828dfe538598..7990ec01c7e8a 100644
--- a/libc/src/__support/FPUtil/gpu/FMA.h
+++ b/libc/src/__support/FPUtil/gpu/FMA.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_FPUTIL_GPU_FMA_H
-#define LLVM_LIBC_SRC_SUPPORT_FPUTIL_GPU_FMA_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_FPUTIL_GPU_FMA_H
+#define LLVM_LIBC_SRC___SUPPORT_FPUTIL_GPU_FMA_H
 
 #include "src/__support/CPP/type_traits.h"
 #include "src/__support/macros/config.h"
@@ -33,4 +33,4 @@ LIBC_INLINE cpp::enable_if_t<cpp::is_same_v<T, double>, T> fma(T x, T y, T z) {
 } // namespace fputil
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_FPUTIL_GPU_FMA_H
+#endif // LLVM_LIBC_SRC___SUPPORT_FPUTIL_GPU_FMA_H
diff --git a/libc/src/__support/FPUtil/multiply_add.h b/libc/src/__support/FPUtil/multiply_add.h
index b45293d976a86..6670a15eb3357 100644
--- a/libc/src/__support/FPUtil/multiply_add.h
+++ b/libc/src/__support/FPUtil/multiply_add.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_FPUTIL_MULTIPLY_ADD_H
-#define LLVM_LIBC_SRC_SUPPORT_FPUTIL_MULTIPLY_ADD_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_FPUTIL_MULTIPLY_ADD_H
+#define LLVM_LIBC_SRC___SUPPORT_FPUTIL_MULTIPLY_ADD_H
 
 #include "src/__support/CPP/type_traits.h"
 #include "src/__support/common.h"
@@ -57,4 +57,4 @@ LIBC_INLINE double multiply_add(double x, double y, double z) {
 
 #endif // LIBC_TARGET_CPU_HAS_FMA
 
-#endif // LLVM_LIBC_SRC_SUPPORT_FPUTIL_MULTIPLY_ADD_H
+#endif // LLVM_LIBC_SRC___SUPPORT_FPUTIL_MULTIPLY_ADD_H
diff --git a/libc/src/__support/FPUtil/nearest_integer.h b/libc/src/__support/FPUtil/nearest_integer.h
index 6d5b8bfbee791..9ccaf55f25312 100644
--- a/libc/src/__support/FPUtil/nearest_integer.h
+++ b/libc/src/__support/FPUtil/nearest_integer.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_FPUTIL_NEAREST_INTEGER_H
-#define LLVM_LIBC_SRC_SUPPORT_FPUTIL_NEAREST_INTEGER_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_FPUTIL_NEAREST_INTEGER_H
+#define LLVM_LIBC_SRC___SUPPORT_FPUTIL_NEAREST_INTEGER_H
 
 #include "src/__support/macros/optimization.h" // LIBC_UNLIKELY
 #include "src/__support/macros/properties/architectures.h"
@@ -63,4 +63,4 @@ LIBC_INLINE double nearest_integer(double x) {
 } // namespace __llvm_libc
 
 #endif
-#endif // LLVM_LIBC_SRC_SUPPORT_FPUTIL_NEAREST_INTEGER_H
+#endif // LLVM_LIBC_SRC___SUPPORT_FPUTIL_NEAREST_INTEGER_H
diff --git a/libc/src/__support/FPUtil/riscv32/FEnvImpl.h b/libc/src/__support/FPUtil/riscv32/FEnvImpl.h
index bb2ffac72af16..05b62dd9580c7 100644
--- a/libc/src/__support/FPUtil/riscv32/FEnvImpl.h
+++ b/libc/src/__support/FPUtil/riscv32/FEnvImpl.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_FPUTIL_RISCV32_FENVIMPL_H
-#define LLVM_LIBC_SRC_SUPPORT_FPUTIL_RISCV32_FENVIMPL_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_FPUTIL_RISCV32_FENVIMPL_H
+#define LLVM_LIBC_SRC___SUPPORT_FPUTIL_RISCV32_FENVIMPL_H
 
 #include "src/__support/FPUtil/FPBits.h"
 #include "src/__support/macros/attributes.h" // For LIBC_INLINE_ASM
@@ -177,4 +177,4 @@ LIBC_INLINE int set_env(const fenv_t *envp) {
 } // namespace fputil
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_FPUTIL_RISCV32_FENVIMPL_H
+#endif // LLVM_LIBC_SRC___SUPPORT_FPUTIL_RISCV32_FENVIMPL_H
diff --git a/libc/src/__support/FPUtil/riscv64/FEnvImpl.h b/libc/src/__support/FPUtil/riscv64/FEnvImpl.h
index b4c11443b798a..2e3c3c76a8d9c 100644
--- a/libc/src/__support/FPUtil/riscv64/FEnvImpl.h
+++ b/libc/src/__support/FPUtil/riscv64/FEnvImpl.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_FPUTIL_RISCV64_FENVIMPL_H
-#define LLVM_LIBC_SRC_SUPPORT_FPUTIL_RISCV64_FENVIMPL_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_FPUTIL_RISCV64_FENVIMPL_H
+#define LLVM_LIBC_SRC___SUPPORT_FPUTIL_RISCV64_FENVIMPL_H
 
 #include "src/__support/FPUtil/FPBits.h"
 #include "src/__support/macros/attributes.h" // For LIBC_INLINE_ASM
@@ -177,4 +177,4 @@ LIBC_INLINE int set_env(const fenv_t *envp) {
 } // namespace fputil
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_FPUTIL_RISCV64_FENVIMPL_H
+#endif // LLVM_LIBC_SRC___SUPPORT_FPUTIL_RISCV64_FENVIMPL_H
diff --git a/libc/src/__support/FPUtil/riscv64/FMA.h b/libc/src/__support/FPUtil/riscv64/FMA.h
index 8f19665300df3..88623a6e86019 100644
--- a/libc/src/__support/FPUtil/riscv64/FMA.h
+++ b/libc/src/__support/FPUtil/riscv64/FMA.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_FPUTIL_RISCV64_FMA_H
-#define LLVM_LIBC_SRC_SUPPORT_FPUTIL_RISCV64_FMA_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_FPUTIL_RISCV64_FMA_H
+#define LLVM_LIBC_SRC___SUPPORT_FPUTIL_RISCV64_FMA_H
 
 #include "src/__support/macros/attributes.h" // LIBC_INLINE
 #include "src/__support/macros/properties/architectures.h"
@@ -47,4 +47,4 @@ LIBC_INLINE cpp::enable_if_t<cpp::is_same_v<T, double>, T> fma(T x, T y, T z) {
 } // namespace fputil
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_FPUTIL_RISCV64_FMA_H
+#endif // LLVM_LIBC_SRC___SUPPORT_FPUTIL_RISCV64_FMA_H
diff --git a/libc/src/__support/FPUtil/riscv64/sqrt.h b/libc/src/__support/FPUtil/riscv64/sqrt.h
index 887000bda7be6..12c9acdc1669c 100644
--- a/libc/src/__support/FPUtil/riscv64/sqrt.h
+++ b/libc/src/__support/FPUtil/riscv64/sqrt.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_FPUTIL_RISCV64_SQRT_H
-#define LLVM_LIBC_SRC_SUPPORT_FPUTIL_RISCV64_SQRT_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_FPUTIL_RISCV64_SQRT_H
+#define LLVM_LIBC_SRC___SUPPORT_FPUTIL_RISCV64_SQRT_H
 
 #include "src/__support/common.h"
 #include "src/__support/macros/properties/architectures.h"
@@ -36,4 +36,4 @@ template <> LIBC_INLINE double sqrt<double>(double x) {
 } // namespace fputil
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_FPUTIL_RISCV64_SQRT_H
+#endif // LLVM_LIBC_SRC___SUPPORT_FPUTIL_RISCV64_SQRT_H
diff --git a/libc/src/__support/FPUtil/rounding_mode.h b/libc/src/__support/FPUtil/rounding_mode.h
index 28e2189ccb012..a11b6b4275060 100644
--- a/libc/src/__support/FPUtil/rounding_mode.h
+++ b/libc/src/__support/FPUtil/rounding_mode.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_FPUTIL_ROUNDING_MODE_H
-#define LLVM_LIBC_SRC_SUPPORT_FPUTIL_ROUNDING_MODE_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_FPUTIL_ROUNDING_MODE_H
+#define LLVM_LIBC_SRC___SUPPORT_FPUTIL_ROUNDING_MODE_H
 
 #include "src/__support/macros/attributes.h" // LIBC_INLINE
 
@@ -76,4 +76,4 @@ LIBC_INLINE int quick_get_round() {
 
 } // namespace __llvm_libc::fputil
 
-#endif // LLVM_LIBC_SRC_SUPPORT_FPUTIL_ROUNDING_MODE_H
+#endif // LLVM_LIBC_SRC___SUPPORT_FPUTIL_ROUNDING_MODE_H
diff --git a/libc/src/__support/FPUtil/sqrt.h b/libc/src/__support/FPUtil/sqrt.h
index 132e7237c810c..521ac4f14d4e5 100644
--- a/libc/src/__support/FPUtil/sqrt.h
+++ b/libc/src/__support/FPUtil/sqrt.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_FPUTIL_SQRT_H
-#define LLVM_LIBC_SRC_SUPPORT_FPUTIL_SQRT_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_FPUTIL_SQRT_H
+#define LLVM_LIBC_SRC___SUPPORT_FPUTIL_SQRT_H
 
 #include "src/__support/macros/properties/architectures.h"
 
@@ -21,4 +21,4 @@
 #include "generic/sqrt.h"
 
 #endif
-#endif // LLVM_LIBC_SRC_SUPPORT_FPUTIL_SQRT_H
+#endif // LLVM_LIBC_SRC___SUPPORT_FPUTIL_SQRT_H
diff --git a/libc/src/__support/FPUtil/triple_double.h b/libc/src/__support/FPUtil/triple_double.h
index b9d527d0686dd..1f85382cc928d 100644
--- a/libc/src/__support/FPUtil/triple_double.h
+++ b/libc/src/__support/FPUtil/triple_double.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_FPUTIL_TRIPLEDOUBLE_H
-#define LLVM_LIBC_SRC_SUPPORT_FPUTIL_TRIPLEDOUBLE_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_FPUTIL_TRIPLE_DOUBLE_H
+#define LLVM_LIBC_SRC___SUPPORT_FPUTIL_TRIPLE_DOUBLE_H
 
 namespace __llvm_libc::fputil {
 
@@ -19,4 +19,4 @@ struct TripleDouble {
 
 } // namespace __llvm_libc::fputil
 
-#endif // LLVM_LIBC_SRC_SUPPORT_FPUTIL_TRIPLEDOUBLE_H
+#endif // LLVM_LIBC_SRC___SUPPORT_FPUTIL_TRIPLE_DOUBLE_H
diff --git a/libc/src/__support/FPUtil/x86_64/FEnvImpl.h b/libc/src/__support/FPUtil/x86_64/FEnvImpl.h
index f657350ff74c4..4380efab778c4 100644
--- a/libc/src/__support/FPUtil/x86_64/FEnvImpl.h
+++ b/libc/src/__support/FPUtil/x86_64/FEnvImpl.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_FPUTIL_X86_64_FENVIMPL_H
-#define LLVM_LIBC_SRC_SUPPORT_FPUTIL_X86_64_FENVIMPL_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_FPUTIL_X86_64_FENVIMPL_H
+#define LLVM_LIBC_SRC___SUPPORT_FPUTIL_X86_64_FENVIMPL_H
 
 #include "src/__support/macros/attributes.h" // LIBC_INLINE
 #include "src/__support/macros/properties/architectures.h"
@@ -644,4 +644,4 @@ LIBC_INLINE int set_env(const fenv_t *envp) {
 } // namespace fputil
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_FPUTIL_X86_64_FENVIMPL_H
+#endif // LLVM_LIBC_SRC___SUPPORT_FPUTIL_X86_64_FENVIMPL_H
diff --git a/libc/src/__support/FPUtil/x86_64/FMA.h b/libc/src/__support/FPUtil/x86_64/FMA.h
index 9953e8335a4cc..b54613a67f438 100644
--- a/libc/src/__support/FPUtil/x86_64/FMA.h
+++ b/libc/src/__support/FPUtil/x86_64/FMA.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_FPUTIL_X86_64_FMA_H
-#define LLVM_LIBC_SRC_SUPPORT_FPUTIL_X86_64_FMA_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_FPUTIL_X86_64_FMA_H
+#define LLVM_LIBC_SRC___SUPPORT_FPUTIL_X86_64_FMA_H
 
 #include "src/__support/macros/attributes.h" // LIBC_INLINE
 #include "src/__support/macros/properties/architectures.h"
@@ -52,4 +52,4 @@ LIBC_INLINE cpp::enable_if_t<cpp::is_same_v<T, double>, T> fma(T x, T y, T z) {
 } // namespace fputil
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_FPUTIL_X86_64_FMA_H
+#endif // LLVM_LIBC_SRC___SUPPORT_FPUTIL_X86_64_FMA_H
diff --git a/libc/src/__support/FPUtil/x86_64/LongDoubleBits.h b/libc/src/__support/FPUtil/x86_64/LongDoubleBits.h
index c8dc6e99177d1..43273ee8864aa 100644
--- a/libc/src/__support/FPUtil/x86_64/LongDoubleBits.h
+++ b/libc/src/__support/FPUtil/x86_64/LongDoubleBits.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_FPUTIL_X86_64_LONG_DOUBLE_BITS_H
-#define LLVM_LIBC_SRC_SUPPORT_FPUTIL_X86_64_LONG_DOUBLE_BITS_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_FPUTIL_X86_64_LONGDOUBLEBITS_H
+#define LLVM_LIBC_SRC___SUPPORT_FPUTIL_X86_64_LONGDOUBLEBITS_H
 
 #include "src/__support/CPP/bit.h"
 #include "src/__support/UInt128.h"
@@ -235,4 +235,4 @@ static_assert(
 } // namespace fputil
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_FPUTIL_X86_64_LONG_DOUBLE_BITS_H
+#endif // LLVM_LIBC_SRC___SUPPORT_FPUTIL_X86_64_LONGDOUBLEBITS_H
diff --git a/libc/src/__support/FPUtil/x86_64/NextAfterLongDouble.h b/libc/src/__support/FPUtil/x86_64/NextAfterLongDouble.h
index 031a083180666..98e90e044509d 100644
--- a/libc/src/__support/FPUtil/x86_64/NextAfterLongDouble.h
+++ b/libc/src/__support/FPUtil/x86_64/NextAfterLongDouble.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_FPUTIL_X86_64_NEXT_AFTER_LONG_DOUBLE_H
-#define LLVM_LIBC_SRC_SUPPORT_FPUTIL_X86_64_NEXT_AFTER_LONG_DOUBLE_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_FPUTIL_X86_64_NEXTAFTERLONGDOUBLE_H
+#define LLVM_LIBC_SRC___SUPPORT_FPUTIL_X86_64_NEXTAFTERLONGDOUBLE_H
 
 #include "src/__support/macros/properties/architectures.h"
 
@@ -119,4 +119,4 @@ LIBC_INLINE long double nextafter(long double from, long double to) {
 } // namespace fputil
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_FPUTIL_X86_64_NEXT_AFTER_LONG_DOUBLE_H
+#endif // LLVM_LIBC_SRC___SUPPORT_FPUTIL_X86_64_NEXTAFTERLONGDOUBLE_H
diff --git a/libc/src/__support/FPUtil/x86_64/PolyEval.h b/libc/src/__support/FPUtil/x86_64/PolyEval.h
index 50f2e06bfa936..81cf965feedf6 100644
--- a/libc/src/__support/FPUtil/x86_64/PolyEval.h
+++ b/libc/src/__support/FPUtil/x86_64/PolyEval.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_FPUTIL_X86_64_POLYEVAL_H
-#define LLVM_LIBC_SRC_SUPPORT_FPUTIL_X86_64_POLYEVAL_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_FPUTIL_X86_64_POLYEVAL_H
+#define LLVM_LIBC_SRC___SUPPORT_FPUTIL_X86_64_POLYEVAL_H
 
 #include "src/__support/common.h"
 #include "src/__support/macros/properties/architectures.h"
@@ -82,4 +82,4 @@ LIBC_INLINE double polyeval(double x, double a0, double a1, double a2,
 } // namespace fputil
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_FPUTIL_X86_64_POLYEVAL_H
+#endif // LLVM_LIBC_SRC___SUPPORT_FPUTIL_X86_64_POLYEVAL_H
diff --git a/libc/src/__support/FPUtil/x86_64/nearest_integer.h b/libc/src/__support/FPUtil/x86_64/nearest_integer.h
index 4541dbf10dc56..a620354333629 100644
--- a/libc/src/__support/FPUtil/x86_64/nearest_integer.h
+++ b/libc/src/__support/FPUtil/x86_64/nearest_integer.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_FPUTIL_X86_64_NEAREST_INTEGER_H
-#define LLVM_LIBC_SRC_SUPPORT_FPUTIL_X86_64_NEAREST_INTEGER_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_FPUTIL_X86_64_NEAREST_INTEGER_H
+#define LLVM_LIBC_SRC___SUPPORT_FPUTIL_X86_64_NEAREST_INTEGER_H
 
 #include "src/__support/common.h"
 #include "src/__support/macros/properties/architectures.h"
@@ -42,4 +42,4 @@ LIBC_INLINE double nearest_integer(double x) {
 } // namespace fputil
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_FPUTIL_X86_64_NEAREST_INTEGER_H
+#endif // LLVM_LIBC_SRC___SUPPORT_FPUTIL_X86_64_NEAREST_INTEGER_H
diff --git a/libc/src/__support/FPUtil/x86_64/sqrt.h b/libc/src/__support/FPUtil/x86_64/sqrt.h
index d445c58eb4be2..324f5907f9aca 100644
--- a/libc/src/__support/FPUtil/x86_64/sqrt.h
+++ b/libc/src/__support/FPUtil/x86_64/sqrt.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_FPUTIL_X86_64_SQRT_H
-#define LLVM_LIBC_SRC_SUPPORT_FPUTIL_X86_64_SQRT_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_FPUTIL_X86_64_SQRT_H
+#define LLVM_LIBC_SRC___SUPPORT_FPUTIL_X86_64_SQRT_H
 
 #include "src/__support/common.h"
 #include "src/__support/macros/properties/architectures.h"
@@ -49,4 +49,4 @@ template <> LIBC_INLINE long double sqrt<long double>(long double x) {
 } // namespace fputil
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_FPUTIL_X86_64_SQRT_H
+#endif // LLVM_LIBC_SRC___SUPPORT_FPUTIL_X86_64_SQRT_H
diff --git a/libc/src/__support/File/dir.h b/libc/src/__support/File/dir.h
index 57d31935551bc..baf57cb52c68c 100644
--- a/libc/src/__support/File/dir.h
+++ b/libc/src/__support/File/dir.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_FILE_DIR_H
-#define LLVM_LIBC_SRC_SUPPORT_FILE_DIR_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_FILE_DIR_H
+#define LLVM_LIBC_SRC___SUPPORT_FILE_DIR_H
 
 #include "src/__support/CPP/span.h"
 #include "src/__support/error_or.h"
@@ -74,4 +74,4 @@ class Dir {
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_FILE_DIR_H
+#endif // LLVM_LIBC_SRC___SUPPORT_FILE_DIR_H
diff --git a/libc/src/__support/File/file.h b/libc/src/__support/File/file.h
index c1c6563fe7b1a..9e65e2a8ecf63 100644
--- a/libc/src/__support/File/file.h
+++ b/libc/src/__support/File/file.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_OSUTIL_FILE_H
-#define LLVM_LIBC_SRC_SUPPORT_OSUTIL_FILE_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_FILE_FILE_H
+#define LLVM_LIBC_SRC___SUPPORT_FILE_FILE_H
 
 #include "src/__support/CPP/new.h"
 #include "src/__support/error_or.h"
@@ -313,4 +313,4 @@ extern File *stderr;
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_OSUTIL_FILE_H
+#endif // LLVM_LIBC_SRC___SUPPORT_FILE_FILE_H
diff --git a/libc/src/__support/File/linux/lseekImpl.h b/libc/src/__support/File/linux/lseekImpl.h
index 8594cd3536fcd..859faf479e486 100644
--- a/libc/src/__support/File/linux/lseekImpl.h
+++ b/libc/src/__support/File/linux/lseekImpl.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_FILE_LINUX_LSEEKIMPL_H
-#define LLVM_LIBC_SRC_SUPPORT_FILE_LINUX_LSEEKIMPL_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_FILE_LINUX_LSEEKIMPL_H
+#define LLVM_LIBC_SRC___SUPPORT_FILE_LINUX_LSEEKIMPL_H
 
 #include "src/__support/OSUtil/syscall.h" // For internal syscall function.
 #include "src/__support/common.h"
@@ -47,4 +47,4 @@ LIBC_INLINE ErrorOr<off_t> lseekimpl(int fd, off_t offset, int whence) {
 } // namespace internal
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_FILE_LINUX_LSEEKIMPL_H
+#endif // LLVM_LIBC_SRC___SUPPORT_FILE_LINUX_LSEEKIMPL_H
diff --git a/libc/src/__support/GPU/amdgpu/utils.h b/libc/src/__support/GPU/amdgpu/utils.h
index f2fa84bc4259f..f64ed796dc177 100644
--- a/libc/src/__support/GPU/amdgpu/utils.h
+++ b/libc/src/__support/GPU/amdgpu/utils.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_GPU_AMDGPU_IO_H
-#define LLVM_LIBC_SRC_SUPPORT_GPU_AMDGPU_IO_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_GPU_AMDGPU_IO_H
+#define LLVM_LIBC_SRC___SUPPORT_GPU_AMDGPU_IO_H
 
 #include "src/__support/common.h"
 #include "src/__support/macros/config.h"
diff --git a/libc/src/__support/GPU/generic/utils.h b/libc/src/__support/GPU/generic/utils.h
index c409f99cc4a8b..af347580cca99 100644
--- a/libc/src/__support/GPU/generic/utils.h
+++ b/libc/src/__support/GPU/generic/utils.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_GPU_GENERIC_IO_H
-#define LLVM_LIBC_SRC_SUPPORT_GPU_GENERIC_IO_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_GPU_GENERIC_IO_H
+#define LLVM_LIBC_SRC___SUPPORT_GPU_GENERIC_IO_H
 
 #include "src/__support/common.h"
 
diff --git a/libc/src/__support/GPU/nvptx/utils.h b/libc/src/__support/GPU/nvptx/utils.h
index dd51f78ffc473..375af6ef10acc 100644
--- a/libc/src/__support/GPU/nvptx/utils.h
+++ b/libc/src/__support/GPU/nvptx/utils.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_GPU_NVPTX_IO_H
-#define LLVM_LIBC_SRC_SUPPORT_GPU_NVPTX_IO_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_GPU_NVPTX_IO_H
+#define LLVM_LIBC_SRC___SUPPORT_GPU_NVPTX_IO_H
 
 #include "src/__support/common.h"
 
diff --git a/libc/src/__support/GPU/utils.h b/libc/src/__support/GPU/utils.h
index 07de9d72fbe62..d598996e0aa25 100644
--- a/libc/src/__support/GPU/utils.h
+++ b/libc/src/__support/GPU/utils.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_GPU_UTIL_H
-#define LLVM_LIBC_SRC_SUPPORT_GPU_UTIL_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_GPU_UTIL_H
+#define LLVM_LIBC_SRC___SUPPORT_GPU_UTIL_H
 
 #include "src/__support/macros/properties/architectures.h"
 
@@ -34,4 +34,4 @@ LIBC_INLINE bool is_first_lane(uint64_t lane_mask) {
 } // namespace gpu
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_OSUTIL_IO_H
+#endif // LLVM_LIBC_SRC___SUPPORT_OSUTIL_IO_H
diff --git a/libc/src/__support/OSUtil/darwin/arm/syscall.h b/libc/src/__support/OSUtil/darwin/arm/syscall.h
index 5b7dc7a3056ef..807ede0e6f982 100644
--- a/libc/src/__support/OSUtil/darwin/arm/syscall.h
+++ b/libc/src/__support/OSUtil/darwin/arm/syscall.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_OSUTIL_DARWIN_ARM_SYSCALL_H
-#define LLVM_LIBC_SRC_SUPPORT_OSUTIL_DARWIN_ARM_SYSCALL_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_OSUTIL_DARWIN_ARM_SYSCALL_H
+#define LLVM_LIBC_SRC___SUPPORT_OSUTIL_DARWIN_ARM_SYSCALL_H
 
 #include "src/__support/common.h"
 
@@ -109,4 +109,4 @@ LIBC_INLINE long syscall_impl(long number, long arg1, long arg2, long arg3,
 #undef REGISTER_CONSTRAINT_5
 #undef REGISTER_CONSTRAINT_6
 
-#endif // LLVM_LIBC_SRC_SUPPORT_OSUTIL_DARWIN_ARM_SYSCALL_H
+#endif // LLVM_LIBC_SRC___SUPPORT_OSUTIL_DARWIN_ARM_SYSCALL_H
diff --git a/libc/src/__support/OSUtil/darwin/io.h b/libc/src/__support/OSUtil/darwin/io.h
index 164d02aacc01a..d29c539048a40 100644
--- a/libc/src/__support/OSUtil/darwin/io.h
+++ b/libc/src/__support/OSUtil/darwin/io.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_OSUTIL_DARWIN_IO_H
-#define LLVM_LIBC_SRC_SUPPORT_OSUTIL_DARWIN_IO_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_OSUTIL_DARWIN_IO_H
+#define LLVM_LIBC_SRC___SUPPORT_OSUTIL_DARWIN_IO_H
 
 #include "src/__support/CPP/string_view.h"
 #include "syscall.h" // For internal syscall function.
@@ -21,4 +21,4 @@ LIBC_INLINE void write_to_stderr(cpp::string_view msg) {
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_OSUTIL_DARWIN_IO_H
+#endif // LLVM_LIBC_SRC___SUPPORT_OSUTIL_DARWIN_IO_H
diff --git a/libc/src/__support/OSUtil/darwin/quick_exit.h b/libc/src/__support/OSUtil/darwin/quick_exit.h
index d58e95ce8dfb9..51b82d945372c 100644
--- a/libc/src/__support/OSUtil/darwin/quick_exit.h
+++ b/libc/src/__support/OSUtil/darwin/quick_exit.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_OSUTIL_DARWIN_QUICK_EXIT_H
-#define LLVM_LIBC_SRC_SUPPORT_OSUTIL_DARWIN_QUICK_EXIT_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_OSUTIL_DARWIN_QUICK_EXIT_H
+#define LLVM_LIBC_SRC___SUPPORT_OSUTIL_DARWIN_QUICK_EXIT_H
 
 #include "syscall.h" // For internal syscall function.
 
@@ -23,4 +23,4 @@ LIBC_INLINE void quick_exit(int status) {
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_OSUTIL_DARWIN_QUICK_EXIT_H
+#endif // LLVM_LIBC_SRC___SUPPORT_OSUTIL_DARWIN_QUICK_EXIT_H
diff --git a/libc/src/__support/OSUtil/darwin/syscall.h b/libc/src/__support/OSUtil/darwin/syscall.h
index b8bd6b2a0bc80..b051745a1e371 100644
--- a/libc/src/__support/OSUtil/darwin/syscall.h
+++ b/libc/src/__support/OSUtil/darwin/syscall.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_OSUTIL_DARWIN_SYSCALL_H
-#define LLVM_LIBC_SRC_SUPPORT_OSUTIL_DARWIN_SYSCALL_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_OSUTIL_DARWIN_SYSCALL_H
+#define LLVM_LIBC_SRC___SUPPORT_OSUTIL_DARWIN_SYSCALL_H
 
 #include "src/__support/CPP/bit.h"
 #include "src/__support/common.h"
@@ -29,4 +29,4 @@ LIBC_INLINE R syscall_impl(long __number, Ts... ts) {
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_OSUTIL_DARWIN_SYSCALL_H
+#endif // LLVM_LIBC_SRC___SUPPORT_OSUTIL_DARWIN_SYSCALL_H
diff --git a/libc/src/__support/OSUtil/fuchsia/io.h b/libc/src/__support/OSUtil/fuchsia/io.h
index 150d92d56eb65..fc794b8593162 100644
--- a/libc/src/__support/OSUtil/fuchsia/io.h
+++ b/libc/src/__support/OSUtil/fuchsia/io.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_OSUTIL_FUCHSIA_IO_H
-#define LLVM_LIBC_SRC_SUPPORT_OSUTIL_FUCHSIA_IO_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_OSUTIL_FUCHSIA_IO_H
+#define LLVM_LIBC_SRC___SUPPORT_OSUTIL_FUCHSIA_IO_H
 
 #ifndef LIBC_COPT_TEST_USE_FUCHSIA
 #error this file should only be used by tests
@@ -25,4 +25,4 @@ LIBC_INLINE void write_to_stderr(cpp::string_view msg) {
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_OSUTIL_FUCHSIA_IO_H
+#endif // LLVM_LIBC_SRC___SUPPORT_OSUTIL_FUCHSIA_IO_H
diff --git a/libc/src/__support/OSUtil/gpu/io.h b/libc/src/__support/OSUtil/gpu/io.h
index a7d15464ccedc..be5daaec55c6b 100644
--- a/libc/src/__support/OSUtil/gpu/io.h
+++ b/libc/src/__support/OSUtil/gpu/io.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_OSUTIL_GPU_IO_H
-#define LLVM_LIBC_SRC_SUPPORT_OSUTIL_GPU_IO_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_OSUTIL_GPU_IO_H
+#define LLVM_LIBC_SRC___SUPPORT_OSUTIL_GPU_IO_H
 
 #include "src/__support/CPP/string_view.h"
 #include "src/__support/macros/attributes.h" // LIBC_INLINE
@@ -18,4 +18,4 @@ void write_to_stderr(cpp::string_view msg);
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_OSUTIL_LINUX_IO_H
+#endif // LLVM_LIBC_SRC___SUPPORT_OSUTIL_LINUX_IO_H
diff --git a/libc/src/__support/OSUtil/gpu/quick_exit.cpp b/libc/src/__support/OSUtil/gpu/quick_exit.cpp
index 3c43f6034b191..a316e2731a01f 100644
--- a/libc/src/__support/OSUtil/gpu/quick_exit.cpp
+++ b/libc/src/__support/OSUtil/gpu/quick_exit.cpp
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_OSUTIL_GPU_QUICK_EXIT_H
-#define LLVM_LIBC_SRC_SUPPORT_OSUTIL_GPU_QUICK_EXIT_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_OSUTIL_GPU_QUICK_EXIT_H
+#define LLVM_LIBC_SRC___SUPPORT_OSUTIL_GPU_QUICK_EXIT_H
 
 #include "quick_exit.h"
 
@@ -30,4 +30,4 @@ void quick_exit(int status) {
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_OSUTIL_GPU_QUICK_EXIT_H
+#endif // LLVM_LIBC_SRC___SUPPORT_OSUTIL_GPU_QUICK_EXIT_H
diff --git a/libc/src/__support/OSUtil/gpu/quick_exit.h b/libc/src/__support/OSUtil/gpu/quick_exit.h
index d07a73a211dad..c4d67e56f32bb 100644
--- a/libc/src/__support/OSUtil/gpu/quick_exit.h
+++ b/libc/src/__support/OSUtil/gpu/quick_exit.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_OSUTIL_GPU_QUICK_EXIT_H
-#define LLVM_LIBC_SRC_SUPPORT_OSUTIL_GPU_QUICK_EXIT_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_OSUTIL_GPU_QUICK_EXIT_H
+#define LLVM_LIBC_SRC___SUPPORT_OSUTIL_GPU_QUICK_EXIT_H
 
 namespace __llvm_libc {
 
@@ -15,4 +15,4 @@ void quick_exit(int status);
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_OSUTIL_GPU_QUICK_EXIT_H
+#endif // LLVM_LIBC_SRC___SUPPORT_OSUTIL_GPU_QUICK_EXIT_H
diff --git a/libc/src/__support/OSUtil/io.h b/libc/src/__support/OSUtil/io.h
index 54b7d051da7c0..fc9d7f3ed38a1 100644
--- a/libc/src/__support/OSUtil/io.h
+++ b/libc/src/__support/OSUtil/io.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_OSUTIL_IO_H
-#define LLVM_LIBC_SRC_SUPPORT_OSUTIL_IO_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_OSUTIL_IO_H
+#define LLVM_LIBC_SRC___SUPPORT_OSUTIL_IO_H
 
 #include "src/__support/macros/properties/architectures.h"
 
@@ -21,4 +21,4 @@
 #include "fuchsia/io.h"
 #endif
 
-#endif // LLVM_LIBC_SRC_SUPPORT_OSUTIL_IO_H
+#endif // LLVM_LIBC_SRC___SUPPORT_OSUTIL_IO_H
diff --git a/libc/src/__support/OSUtil/linux/aarch64/syscall.h b/libc/src/__support/OSUtil/linux/aarch64/syscall.h
index 350e39f3bd5f9..1d0ed9acedea0 100644
--- a/libc/src/__support/OSUtil/linux/aarch64/syscall.h
+++ b/libc/src/__support/OSUtil/linux/aarch64/syscall.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_OSUTIL_LINUX_AARCH64_SYSCALL_H
-#define LLVM_LIBC_SRC_SUPPORT_OSUTIL_LINUX_AARCH64_SYSCALL_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_OSUTIL_LINUX_AARCH64_SYSCALL_H
+#define LLVM_LIBC_SRC___SUPPORT_OSUTIL_LINUX_AARCH64_SYSCALL_H
 
 #include "src/__support/common.h"
 
@@ -107,4 +107,4 @@ LIBC_INLINE long syscall_impl(long number, long arg1, long arg2, long arg3,
 #undef REGISTER_CONSTRAINT_5
 #undef REGISTER_CONSTRAINT_6
 
-#endif // LLVM_LIBC_SRC_SUPPORT_OSUTIL_LINUX_AARCH64_SYSCALL_H
+#endif // LLVM_LIBC_SRC___SUPPORT_OSUTIL_LINUX_AARCH64_SYSCALL_H
diff --git a/libc/src/__support/OSUtil/linux/arm/syscall.h b/libc/src/__support/OSUtil/linux/arm/syscall.h
index 325600e6d424a..351a1c05aae19 100644
--- a/libc/src/__support/OSUtil/linux/arm/syscall.h
+++ b/libc/src/__support/OSUtil/linux/arm/syscall.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_OSUTIL_LINUX_ARM_SYSCALL_H
-#define LLVM_LIBC_SRC_SUPPORT_OSUTIL_LINUX_ARM_SYSCALL_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_OSUTIL_LINUX_ARM_SYSCALL_H
+#define LLVM_LIBC_SRC___SUPPORT_OSUTIL_LINUX_ARM_SYSCALL_H
 
 #include "src/__support/common.h"
 
@@ -113,4 +113,4 @@ LIBC_INLINE long syscall_impl(long number, long arg1, long arg2, long arg3,
 #undef REGISTER_CONSTRAINT_5
 #undef REGISTER_CONSTRAINT_6
 
-#endif // LLVM_LIBC_SRC_SUPPORT_OSUTIL_LINUX_ARM_SYSCALL_H
+#endif // LLVM_LIBC_SRC___SUPPORT_OSUTIL_LINUX_ARM_SYSCALL_H
diff --git a/libc/src/__support/OSUtil/linux/io.h b/libc/src/__support/OSUtil/linux/io.h
index 13a7aa072ad7b..b20be45113786 100644
--- a/libc/src/__support/OSUtil/linux/io.h
+++ b/libc/src/__support/OSUtil/linux/io.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_OSUTIL_LINUX_IO_H
-#define LLVM_LIBC_SRC_SUPPORT_OSUTIL_LINUX_IO_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_OSUTIL_LINUX_IO_H
+#define LLVM_LIBC_SRC___SUPPORT_OSUTIL_LINUX_IO_H
 
 #include "src/__support/CPP/string_view.h"
 #include "syscall.h" // For internal syscall function.
@@ -23,4 +23,4 @@ LIBC_INLINE void write_to_stderr(cpp::string_view msg) {
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_OSUTIL_LINUX_IO_H
+#endif // LLVM_LIBC_SRC___SUPPORT_OSUTIL_LINUX_IO_H
diff --git a/libc/src/__support/OSUtil/linux/quick_exit.h b/libc/src/__support/OSUtil/linux/quick_exit.h
index a369764915935..2e2d86d634d06 100644
--- a/libc/src/__support/OSUtil/linux/quick_exit.h
+++ b/libc/src/__support/OSUtil/linux/quick_exit.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_OSUTIL_LINUX_QUICK_EXIT_H
-#define LLVM_LIBC_SRC_SUPPORT_OSUTIL_LINUX_QUICK_EXIT_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_OSUTIL_LINUX_QUICK_EXIT_H
+#define LLVM_LIBC_SRC___SUPPORT_OSUTIL_LINUX_QUICK_EXIT_H
 
 #include "syscall.h"             // For internal syscall function.
 
@@ -26,4 +26,4 @@ LIBC_INLINE void quick_exit(int status) {
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_OSUTIL_LINUX_QUICK_EXIT_H
+#endif // LLVM_LIBC_SRC___SUPPORT_OSUTIL_LINUX_QUICK_EXIT_H
diff --git a/libc/src/__support/OSUtil/linux/riscv64/syscall.h b/libc/src/__support/OSUtil/linux/riscv64/syscall.h
index c9d2a39941a64..e307bcb8f1dbd 100644
--- a/libc/src/__support/OSUtil/linux/riscv64/syscall.h
+++ b/libc/src/__support/OSUtil/linux/riscv64/syscall.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_OSUTIL_LINUX_RISCV64_SYSCALL_H
-#define LLVM_LIBC_SRC_SUPPORT_OSUTIL_LINUX_RISCV64_SYSCALL_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_OSUTIL_LINUX_RISCV64_SYSCALL_H
+#define LLVM_LIBC_SRC___SUPPORT_OSUTIL_LINUX_RISCV64_SYSCALL_H
 
 #include "src/__support/common.h"
 
@@ -107,4 +107,4 @@ LIBC_INLINE long syscall_impl(long number, long arg1, long arg2, long arg3,
 #undef REGISTER_CONSTRAINT_5
 #undef REGISTER_CONSTRAINT_6
 
-#endif // LLVM_LIBC_SRC_SUPPORT_OSUTIL_LINUX_RISCV64_SYSCALL_H
+#endif // LLVM_LIBC_SRC___SUPPORT_OSUTIL_LINUX_RISCV64_SYSCALL_H
diff --git a/libc/src/__support/OSUtil/linux/syscall.h b/libc/src/__support/OSUtil/linux/syscall.h
index 1ab62e6de45ea..8a1fbb34189b8 100644
--- a/libc/src/__support/OSUtil/linux/syscall.h
+++ b/libc/src/__support/OSUtil/linux/syscall.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_OSUTIL_LINUX_SYSCALL_H
-#define LLVM_LIBC_SRC_SUPPORT_OSUTIL_LINUX_SYSCALL_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_OSUTIL_LINUX_SYSCALL_H
+#define LLVM_LIBC_SRC___SUPPORT_OSUTIL_LINUX_SYSCALL_H
 
 #include "src/__support/CPP/bit.h"
 #include "src/__support/common.h"
@@ -33,4 +33,4 @@ LIBC_INLINE R syscall_impl(long __number, Ts... ts) {
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_OSUTIL_LINUX_SYSCALL_H
+#endif // LLVM_LIBC_SRC___SUPPORT_OSUTIL_LINUX_SYSCALL_H
diff --git a/libc/src/__support/OSUtil/linux/x86_64/syscall.h b/libc/src/__support/OSUtil/linux/x86_64/syscall.h
index 1a5cb0a628a81..bf2d2cd7351dd 100644
--- a/libc/src/__support/OSUtil/linux/x86_64/syscall.h
+++ b/libc/src/__support/OSUtil/linux/x86_64/syscall.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_OSUTIL_LINUX_X86_64_SYSCALL_H
-#define LLVM_LIBC_SRC_SUPPORT_OSUTIL_LINUX_X86_64_SYSCALL_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_OSUTIL_LINUX_X86_64_SYSCALL_H
+#define LLVM_LIBC_SRC___SUPPORT_OSUTIL_LINUX_X86_64_SYSCALL_H
 
 #include "src/__support/common.h"
 
@@ -95,4 +95,4 @@ LIBC_INLINE long syscall_impl(long __number, long __arg1, long __arg2,
 #undef SYSCALL_CLOBBER_LIST
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_OSUTIL_LINUX_X86_64_SYSCALL_H
+#endif // LLVM_LIBC_SRC___SUPPORT_OSUTIL_LINUX_X86_64_SYSCALL_H
diff --git a/libc/src/__support/OSUtil/quick_exit.h b/libc/src/__support/OSUtil/quick_exit.h
index 4001e0bcda687..4329df8ecef05 100644
--- a/libc/src/__support/OSUtil/quick_exit.h
+++ b/libc/src/__support/OSUtil/quick_exit.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_OSUTIL_QUICK_EXIT_H
-#define LLVM_LIBC_SRC_SUPPORT_OSUTIL_QUICK_EXIT_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_OSUTIL_QUICK_EXIT_H
+#define LLVM_LIBC_SRC___SUPPORT_OSUTIL_QUICK_EXIT_H
 
 #include "src/__support/macros/properties/architectures.h"
 
@@ -19,4 +19,4 @@
 #include "linux/quick_exit.h"
 #endif
 
-#endif // LLVM_LIBC_SRC_SUPPORT_OSUTIL_QUICK_EXIT_H
+#endif // LLVM_LIBC_SRC___SUPPORT_OSUTIL_QUICK_EXIT_H
diff --git a/libc/src/__support/OSUtil/syscall.h b/libc/src/__support/OSUtil/syscall.h
index 6ec9f070a48e3..fc697a7c09821 100644
--- a/libc/src/__support/OSUtil/syscall.h
+++ b/libc/src/__support/OSUtil/syscall.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_OSUTIL_SYSCALL_H
-#define LLVM_LIBC_SRC_SUPPORT_OSUTIL_SYSCALL_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_OSUTIL_SYSCALL_H
+#define LLVM_LIBC_SRC___SUPPORT_OSUTIL_SYSCALL_H
 
 #ifdef __APPLE__
 #include "darwin/syscall.h"
@@ -15,4 +15,4 @@
 #include "linux/syscall.h"
 #endif
 
-#endif // LLVM_LIBC_SRC_SUPPORT_OSUTIL_SYSCALL_H
+#endif // LLVM_LIBC_SRC___SUPPORT_OSUTIL_SYSCALL_H
diff --git a/libc/src/__support/RPC/rpc.h b/libc/src/__support/RPC/rpc.h
index fc95e5edf1c72..7cece9615f607 100644
--- a/libc/src/__support/RPC/rpc.h
+++ b/libc/src/__support/RPC/rpc.h
@@ -15,8 +15,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_RPC_RPC_H
-#define LLVM_LIBC_SRC_SUPPORT_RPC_RPC_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_RPC_RPC_H
+#define LLVM_LIBC_SRC___SUPPORT_RPC_RPC_H
 
 #include "rpc_util.h"
 #include "src/__support/CPP/algorithm.h" // max
diff --git a/libc/src/__support/RPC/rpc_client.h b/libc/src/__support/RPC/rpc_client.h
index 4a07b9507fc0f..3b36c4fffc9e8 100644
--- a/libc/src/__support/RPC/rpc_client.h
+++ b/libc/src/__support/RPC/rpc_client.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_RPC_RPC_CLIENT_H
-#define LLVM_LIBC_SRC_SUPPORT_RPC_RPC_CLIENT_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_RPC_RPC_CLIENT_H
+#define LLVM_LIBC_SRC___SUPPORT_RPC_RPC_CLIENT_H
 
 #include "rpc.h"
 
diff --git a/libc/src/__support/RPC/rpc_util.h b/libc/src/__support/RPC/rpc_util.h
index 8f500369541de..999fd902adf62 100644
--- a/libc/src/__support/RPC/rpc_util.h
+++ b/libc/src/__support/RPC/rpc_util.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_RPC_RPC_UTILS_H
-#define LLVM_LIBC_SRC_SUPPORT_RPC_RPC_UTILS_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_RPC_RPC_UTILS_H
+#define LLVM_LIBC_SRC___SUPPORT_RPC_RPC_UTILS_H
 
 #include "src/__support/CPP/type_traits.h"
 #include "src/__support/GPU/utils.h"
diff --git a/libc/src/__support/StringUtil/error_to_string.h b/libc/src/__support/StringUtil/error_to_string.h
index 36c37e244691c..7981aa9b9a96e 100644
--- a/libc/src/__support/StringUtil/error_to_string.h
+++ b/libc/src/__support/StringUtil/error_to_string.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_ERROR_TO_STRING_H
-#define LLVM_LIBC_SRC_SUPPORT_ERROR_TO_STRING_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_STRINGUTIL_ERROR_TO_STRING_H
+#define LLVM_LIBC_SRC___SUPPORT_STRINGUTIL_ERROR_TO_STRING_H
 
 #include "src/__support/CPP/span.h"
 #include "src/__support/CPP/string_view.h"
@@ -20,4 +20,4 @@ cpp::string_view get_error_string(int err_num, cpp::span<char> buffer);
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_ERROR_TO_STRING_H
+#endif // LLVM_LIBC_SRC___SUPPORT_STRINGUTIL_ERROR_TO_STRING_H
diff --git a/libc/src/__support/StringUtil/message_mapper.h b/libc/src/__support/StringUtil/message_mapper.h
index f73b8de6cc57e..a190037462f11 100644
--- a/libc/src/__support/StringUtil/message_mapper.h
+++ b/libc/src/__support/StringUtil/message_mapper.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_STRING_UTIL_MESSAGE_MAPPER_H
-#define LLVM_LIBC_SRC_SUPPORT_STRING_UTIL_MESSAGE_MAPPER_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_STRING_UTIL_MESSAGE_MAPPER_H
+#define LLVM_LIBC_SRC___SUPPORT_STRING_UTIL_MESSAGE_MAPPER_H
 
 #include "src/__support/CPP/array.h"
 #include "src/__support/CPP/optional.h"
@@ -100,4 +100,4 @@ constexpr MsgTable<N1 + N2> operator+(const MsgTable<N1> &t1,
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_STRING_UTIL_MESSAGE_MAPPER_H
+#endif // LLVM_LIBC_SRC___SUPPORT_STRING_UTIL_MESSAGE_MAPPER_H
diff --git a/libc/src/__support/StringUtil/platform_errors.h b/libc/src/__support/StringUtil/platform_errors.h
index 8ca3baee421b5..dfa841ce5d823 100644
--- a/libc/src/__support/StringUtil/platform_errors.h
+++ b/libc/src/__support/StringUtil/platform_errors.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_STRING_UTIL_PLATFORM_ERROR_TABLE_H
-#define LLVM_LIBC_SRC_SUPPORT_STRING_UTIL_PLATFORM_ERROR_TABLE_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_STRING_UTIL_PLATFORM_ERROR_TABLE_H
+#define LLVM_LIBC_SRC___SUPPORT_STRING_UTIL_PLATFORM_ERROR_TABLE_H
 
 #if defined(__linux__) || defined(__Fuchsia__)
 #include "tables/linux_platform_errors.h"
@@ -15,4 +15,4 @@
 #include "tables/minimal_platform_errors.h"
 #endif
 
-#endif // LLVM_LIBC_SRC_SUPPORT_STRING_UTIL_PLATFORM_ERROR_TABLE_H
+#endif // LLVM_LIBC_SRC___SUPPORT_STRING_UTIL_PLATFORM_ERROR_TABLE_H
diff --git a/libc/src/__support/StringUtil/platform_signals.h b/libc/src/__support/StringUtil/platform_signals.h
index eef0d3ddefaed..0a1c3f6bef251 100644
--- a/libc/src/__support/StringUtil/platform_signals.h
+++ b/libc/src/__support/StringUtil/platform_signals.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_STRING_UTIL_PLATFORM_SIGNAL_TABLE_H
-#define LLVM_LIBC_SRC_SUPPORT_STRING_UTIL_PLATFORM_SIGNAL_TABLE_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_STRING_UTIL_PLATFORM_SIGNAL_TABLE_H
+#define LLVM_LIBC_SRC___SUPPORT_STRING_UTIL_PLATFORM_SIGNAL_TABLE_H
 
 #if defined(__linux__) || defined(__Fuchsia__)
 #include "tables/linux_platform_signals.h"
@@ -15,4 +15,4 @@
 #include "tables/minimal_platform_signals.h"
 #endif
 
-#endif // LLVM_LIBC_SRC_SUPPORT_STRING_UTIL_PLATFORM_SIGNAL_TABLE_H
+#endif // LLVM_LIBC_SRC___SUPPORT_STRING_UTIL_PLATFORM_SIGNAL_TABLE_H
diff --git a/libc/src/__support/StringUtil/signal_to_string.h b/libc/src/__support/StringUtil/signal_to_string.h
index 694015336b41c..11ec33a0a07c6 100644
--- a/libc/src/__support/StringUtil/signal_to_string.h
+++ b/libc/src/__support/StringUtil/signal_to_string.h
@@ -6,12 +6,13 @@
 //
 //===----------------------------------------------------------------------===//
 
+
+#ifndef LLVM_LIBC_SRC___SUPPORT_STRINGUTIL_SIGNAL_TO_STRING_H
+#define LLVM_LIBC_SRC___SUPPORT_STRINGUTIL_SIGNAL_TO_STRING_H
+
 #include "src/__support/CPP/span.h"
 #include "src/__support/CPP/string_view.h"
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_SIGNAL_TO_STRING_H
-#define LLVM_LIBC_SRC_SUPPORT_SIGNAL_TO_STRING_H
-
 namespace __llvm_libc {
 
 cpp::string_view get_signal_string(int err_num);
@@ -20,4 +21,4 @@ cpp::string_view get_signal_string(int err_num, cpp::span<char> buffer);
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_SIGNAL_TO_STRING_H
+#endif // LLVM_LIBC_SRC___SUPPORT_STRINGUTIL_SIGNAL_TO_STRING_H
diff --git a/libc/src/__support/StringUtil/tables/linux_extension_errors.h b/libc/src/__support/StringUtil/tables/linux_extension_errors.h
index 632c563241021..5440c8e371540 100644
--- a/libc/src/__support/StringUtil/tables/linux_extension_errors.h
+++ b/libc/src/__support/StringUtil/tables/linux_extension_errors.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_STRING_UTIL_TABLES_LINUX_EXTENSION_ERRORS_H
-#define LLVM_LIBC_SRC_SUPPORT_STRING_UTIL_TABLES_LINUX_EXTENSION_ERRORS_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_STRING_UTIL_TABLES_LINUX_EXTENSION_ERRORS_H
+#define LLVM_LIBC_SRC___SUPPORT_STRING_UTIL_TABLES_LINUX_EXTENSION_ERRORS_H
 
 #include "src/__support/StringUtil/message_mapper.h"
 
@@ -72,4 +72,4 @@ constexpr MsgTable<52> LINUX_ERRORS = {
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_STRING_UTIL_TABLES_LINUX_EXTENSION_ERRORS_H
+#endif // LLVM_LIBC_SRC___SUPPORT_STRING_UTIL_TABLES_LINUX_EXTENSION_ERRORS_H
diff --git a/libc/src/__support/StringUtil/tables/linux_extension_signals.h b/libc/src/__support/StringUtil/tables/linux_extension_signals.h
index 8da3731e39872..fd17881d4f780 100644
--- a/libc/src/__support/StringUtil/tables/linux_extension_signals.h
+++ b/libc/src/__support/StringUtil/tables/linux_extension_signals.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_STRING_UTIL_TABLES_LINUX_EXTENSION_SIGNALS_H
-#define LLVM_LIBC_SRC_SUPPORT_STRING_UTIL_TABLES_LINUX_EXTENSION_SIGNALS_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_STRING_UTIL_TABLES_LINUX_EXTENSION_SIGNALS_H
+#define LLVM_LIBC_SRC___SUPPORT_STRING_UTIL_TABLES_LINUX_EXTENSION_SIGNALS_H
 
 #include "src/__support/StringUtil/message_mapper.h"
 
@@ -30,4 +30,4 @@ LIBC_INLINE_VAR constexpr const MsgTable<3> LINUX_SIGNALS = {
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_STRING_UTIL_TABLES_LINUX_EXTENSION_SIGNALS_H
+#endif // LLVM_LIBC_SRC___SUPPORT_STRING_UTIL_TABLES_LINUX_EXTENSION_SIGNALS_H
diff --git a/libc/src/__support/StringUtil/tables/linux_platform_errors.h b/libc/src/__support/StringUtil/tables/linux_platform_errors.h
index 49e4b1bd2a428..3139a1f1c5b38 100644
--- a/libc/src/__support/StringUtil/tables/linux_platform_errors.h
+++ b/libc/src/__support/StringUtil/tables/linux_platform_errors.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_STRING_UTIL_TABLES_LINUX_PLATFORM_ERRORS_H
-#define LLVM_LIBC_SRC_SUPPORT_STRING_UTIL_TABLES_LINUX_PLATFORM_ERRORS_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_STRING_UTIL_TABLES_LINUX_PLATFORM_ERRORS_H
+#define LLVM_LIBC_SRC___SUPPORT_STRING_UTIL_TABLES_LINUX_PLATFORM_ERRORS_H
 
 #include "linux_extension_errors.h"
 #include "posix_errors.h"
@@ -20,4 +20,4 @@ LIBC_INLINE_VAR constexpr auto PLATFORM_ERRORS =
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_STRING_UTIL_TABLES_LINUX_PLATFORM_ERRORS_H
+#endif // LLVM_LIBC_SRC___SUPPORT_STRING_UTIL_TABLES_LINUX_PLATFORM_ERRORS_H
diff --git a/libc/src/__support/StringUtil/tables/linux_platform_signals.h b/libc/src/__support/StringUtil/tables/linux_platform_signals.h
index b21b0ccf89aef..b08517426445a 100644
--- a/libc/src/__support/StringUtil/tables/linux_platform_signals.h
+++ b/libc/src/__support/StringUtil/tables/linux_platform_signals.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_STRING_UTIL_TABLES_LINUX_PLATFORM_SIGNALS_H
-#define LLVM_LIBC_SRC_SUPPORT_STRING_UTIL_TABLES_LINUX_PLATFORM_SIGNALS_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_STRING_UTIL_TABLES_LINUX_PLATFORM_SIGNALS_H
+#define LLVM_LIBC_SRC___SUPPORT_STRING_UTIL_TABLES_LINUX_PLATFORM_SIGNALS_H
 
 #include "linux_extension_signals.h"
 #include "posix_signals.h"
@@ -20,4 +20,4 @@ LIBC_INLINE_VAR constexpr auto PLATFORM_SIGNALS =
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_STRING_UTIL_TABLES_LINUX_PLATFORM_SIGNALS_H
+#endif // LLVM_LIBC_SRC___SUPPORT_STRING_UTIL_TABLES_LINUX_PLATFORM_SIGNALS_H
diff --git a/libc/src/__support/StringUtil/tables/minimal_platform_errors.h b/libc/src/__support/StringUtil/tables/minimal_platform_errors.h
index 950b84be20499..fa164db91ceed 100644
--- a/libc/src/__support/StringUtil/tables/minimal_platform_errors.h
+++ b/libc/src/__support/StringUtil/tables/minimal_platform_errors.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_STRING_UTIL_TABLES_MINIMAL_PLATFORM_ERRORS_H
-#define LLVM_LIBC_SRC_SUPPORT_STRING_UTIL_TABLES_MINIMAL_PLATFORM_ERRORS_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_STRING_UTIL_TABLES_MINIMAL_PLATFORM_ERRORS_H
+#define LLVM_LIBC_SRC___SUPPORT_STRING_UTIL_TABLES_MINIMAL_PLATFORM_ERRORS_H
 
 #include "stdc_errors.h"
 
@@ -17,4 +17,4 @@ LIBC_INLINE_VAR constexpr auto PLATFORM_ERRORS = STDC_ERRORS;
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_STRING_UTIL_TABLES_MINIMAL_PLATFORM_ERRORS_H
+#endif // LLVM_LIBC_SRC___SUPPORT_STRING_UTIL_TABLES_MINIMAL_PLATFORM_ERRORS_H
diff --git a/libc/src/__support/StringUtil/tables/minimal_platform_signals.h b/libc/src/__support/StringUtil/tables/minimal_platform_signals.h
index e1a77803895f1..a6d59e5de45f1 100644
--- a/libc/src/__support/StringUtil/tables/minimal_platform_signals.h
+++ b/libc/src/__support/StringUtil/tables/minimal_platform_signals.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_STRING_UTIL_TABLES_MINIMAL_PLATFORM_SIGNALS_H
-#define LLVM_LIBC_SRC_SUPPORT_STRING_UTIL_TABLES_MINIMAL_PLATFORM_SIGNALS_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_STRING_UTIL_TABLES_MINIMAL_PLATFORM_SIGNALS_H
+#define LLVM_LIBC_SRC___SUPPORT_STRING_UTIL_TABLES_MINIMAL_PLATFORM_SIGNALS_H
 
 #include "stdc_signals.h"
 
@@ -17,4 +17,4 @@ LIBC_INLINE_VAR constexpr auto PLATFORM_SIGNALS = STDC_SIGNALS;
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_STRING_UTIL_TABLES_MINIMAL_PLATFORM_SIGNALS_H
+#endif // LLVM_LIBC_SRC___SUPPORT_STRING_UTIL_TABLES_MINIMAL_PLATFORM_SIGNALS_H
diff --git a/libc/src/__support/StringUtil/tables/posix_errors.h b/libc/src/__support/StringUtil/tables/posix_errors.h
index 01a0f223d6679..59ed279c47810 100644
--- a/libc/src/__support/StringUtil/tables/posix_errors.h
+++ b/libc/src/__support/StringUtil/tables/posix_errors.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_STRING_UTIL_TABLES_POSIX_ERRORS_H
-#define LLVM_LIBC_SRC_SUPPORT_STRING_UTIL_TABLES_POSIX_ERRORS_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_STRING_UTIL_TABLES_POSIX_ERRORS_H
+#define LLVM_LIBC_SRC___SUPPORT_STRING_UTIL_TABLES_POSIX_ERRORS_H
 
 #include "src/__support/StringUtil/message_mapper.h"
 
@@ -96,4 +96,4 @@ LIBC_INLINE_VAR constexpr MsgTable<76> POSIX_ERRORS = {
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_STRING_UTIL_TABLES_POSIX_ERRORS_H
+#endif // LLVM_LIBC_SRC___SUPPORT_STRING_UTIL_TABLES_POSIX_ERRORS_H
diff --git a/libc/src/__support/StringUtil/tables/posix_signals.h b/libc/src/__support/StringUtil/tables/posix_signals.h
index a7e681b92449c..beaa18bff87f3 100644
--- a/libc/src/__support/StringUtil/tables/posix_signals.h
+++ b/libc/src/__support/StringUtil/tables/posix_signals.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_STRING_UTIL_TABLES_POSIX_SIGNALS_H
-#define LLVM_LIBC_SRC_SUPPORT_STRING_UTIL_TABLES_POSIX_SIGNALS_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_STRING_UTIL_TABLES_POSIX_SIGNALS_H
+#define LLVM_LIBC_SRC___SUPPORT_STRING_UTIL_TABLES_POSIX_SIGNALS_H
 
 #include "src/__support/CPP/array.h"
 #include "src/__support/StringUtil/message_mapper.h"
@@ -43,4 +43,4 @@ LIBC_INLINE_VAR constexpr MsgTable<22> POSIX_SIGNALS = {
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_STRING_UTIL_TABLES_POSIX_SIGNALS_H
+#endif // LLVM_LIBC_SRC___SUPPORT_STRING_UTIL_TABLES_POSIX_SIGNALS_H
diff --git a/libc/src/__support/StringUtil/tables/signal_table.h b/libc/src/__support/StringUtil/tables/signal_table.h
index 6e198a60c9b32..87b5abf5e0977 100644
--- a/libc/src/__support/StringUtil/tables/signal_table.h
+++ b/libc/src/__support/StringUtil/tables/signal_table.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_STRING_UTIL_TABLES_SIGNAL_TABLE_H
-#define LLVM_LIBC_SRC_SUPPORT_STRING_UTIL_TABLES_SIGNAL_TABLE_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_STRING_UTIL_TABLES_SIGNAL_TABLE_H
+#define LLVM_LIBC_SRC___SUPPORT_STRING_UTIL_TABLES_SIGNAL_TABLE_H
 
 #include "src/__support/StringUtil/message_mapper.h"
 
@@ -36,4 +36,4 @@ LIBC_INLINE_VAR constexpr auto PLATFORM_SIGNALS = []() {
 
 } // namespace __llvm_libc::internal
 
-#endif // LLVM_LIBC_SRC_SUPPORT_STRING_UTIL_TABLES_SIGNAL_TABLE_H
+#endif // LLVM_LIBC_SRC___SUPPORT_STRING_UTIL_TABLES_SIGNAL_TABLE_H
diff --git a/libc/src/__support/StringUtil/tables/stdc_errors.h b/libc/src/__support/StringUtil/tables/stdc_errors.h
index 42d370583d753..054c4ffdc7add 100644
--- a/libc/src/__support/StringUtil/tables/stdc_errors.h
+++ b/libc/src/__support/StringUtil/tables/stdc_errors.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_STRING_UTIL_TABLES_STDC_ERRORS_H
-#define LLVM_LIBC_SRC_SUPPORT_STRING_UTIL_TABLES_STDC_ERRORS_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_STRING_UTIL_TABLES_STDC_ERRORS_H
+#define LLVM_LIBC_SRC___SUPPORT_STRING_UTIL_TABLES_STDC_ERRORS_H
 
 #include "src/__support/StringUtil/message_mapper.h"
 
@@ -24,4 +24,4 @@ LIBC_INLINE_VAR constexpr const MsgTable<4> STDC_ERRORS = {
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_STRING_UTIL_TABLES_LINUX_ERRORS_H
+#endif // LLVM_LIBC_SRC___SUPPORT_STRING_UTIL_TABLES_LINUX_ERRORS_H
diff --git a/libc/src/__support/StringUtil/tables/stdc_signals.h b/libc/src/__support/StringUtil/tables/stdc_signals.h
index 13b1aeda124bd..0bc288db3c449 100644
--- a/libc/src/__support/StringUtil/tables/stdc_signals.h
+++ b/libc/src/__support/StringUtil/tables/stdc_signals.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_STRING_UTIL_TABLES_STDC_SIGNALS_H
-#define LLVM_LIBC_SRC_SUPPORT_STRING_UTIL_TABLES_STDC_SIGNALS_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_STRING_UTIL_TABLES_STDC_SIGNALS_H
+#define LLVM_LIBC_SRC___SUPPORT_STRING_UTIL_TABLES_STDC_SIGNALS_H
 
 #include <signal.h> // For signal numbers
 
@@ -26,4 +26,4 @@ LIBC_INLINE_VAR constexpr const MsgTable<6> STDC_SIGNALS = {
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_STRING_UTIL_TABLES_LINUX_SIGNALS_H
+#endif // LLVM_LIBC_SRC___SUPPORT_STRING_UTIL_TABLES_LINUX_SIGNALS_H
diff --git a/libc/src/__support/UInt.h b/libc/src/__support/UInt.h
index 507b8587006f6..6310c8925c40d 100644
--- a/libc/src/__support/UInt.h
+++ b/libc/src/__support/UInt.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_UINT_H
-#define LLVM_LIBC_SRC_SUPPORT_UINT_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_UINT_H
+#define LLVM_LIBC_SRC___SUPPORT_UINT_H
 
 #include "src/__support/CPP/array.h"
 #include "src/__support/CPP/limits.h"
@@ -929,4 +929,4 @@ struct make_signed<UInt<Bits>> : type_identity<Int<Bits>> {
 
 } // namespace __llvm_libc::cpp
 
-#endif // LLVM_LIBC_SRC_SUPPORT_UINT_H
+#endif // LLVM_LIBC_SRC___SUPPORT_UINT_H
diff --git a/libc/src/__support/UInt128.h b/libc/src/__support/UInt128.h
index 1cc86a7c3fe06..2df4e5263bc16 100644
--- a/libc/src/__support/UInt128.h
+++ b/libc/src/__support/UInt128.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_UINT128_H
-#define LLVM_LIBC_SRC_SUPPORT_UINT128_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_UINT128_H
+#define LLVM_LIBC_SRC___SUPPORT_UINT128_H
 
 #include "UInt.h"
 
@@ -19,4 +19,4 @@ using UInt128 = __uint128_t;
 using Int128 = __int128_t;
 #endif
 
-#endif // LLVM_LIBC_SRC_SUPPORT_UINT128_H
+#endif // LLVM_LIBC_SRC___SUPPORT_UINT128_H
diff --git a/libc/src/__support/arg_list.h b/libc/src/__support/arg_list.h
index 43cf8352f4b46..e415415492416 100644
--- a/libc/src/__support/arg_list.h
+++ b/libc/src/__support/arg_list.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_ARG_LIST_H
-#define LLVM_LIBC_SRC_SUPPORT_ARG_LIST_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_ARG_LIST_H
+#define LLVM_LIBC_SRC___SUPPORT_ARG_LIST_H
 
 #include "src/__support/common.h"
 
@@ -63,4 +63,4 @@ class MockArgList {
 } // namespace internal
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_ARG_LIST_H
+#endif // LLVM_LIBC_SRC___SUPPORT_ARG_LIST_H
diff --git a/libc/src/__support/blockstore.h b/libc/src/__support/blockstore.h
index 16165c5e64893..cdef80b1675b8 100644
--- a/libc/src/__support/blockstore.h
+++ b/libc/src/__support/blockstore.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SUPPORT_BLOCKSTORE_H
-#define LLVM_LIBC_SUPPORT_BLOCKSTORE_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_BLOCKSTORE_H
+#define LLVM_LIBC_SRC___SUPPORT_BLOCKSTORE_H
 
 #include <src/__support/CPP/new.h>
 #include <src/__support/libc_assert.h>
@@ -206,4 +206,4 @@ using ReverseOrderBlockStore = BlockStore<T, BLOCK_SIZE, true>;
 } // namespace cpp
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SUPPORT_BLOCKSTORE_H
+#endif // LLVM_LIBC_SRC___SUPPORT_BLOCKSTORE_H
diff --git a/libc/src/__support/builtin_wrappers.h b/libc/src/__support/builtin_wrappers.h
index a06f859aa6301..1da9cee4ad9f1 100644
--- a/libc/src/__support/builtin_wrappers.h
+++ b/libc/src/__support/builtin_wrappers.h
@@ -7,8 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_BUILTIN_WRAPPERS_H
-#define LLVM_LIBC_SRC_SUPPORT_BUILTIN_WRAPPERS_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_BUILTIN_WRAPPERS_H
+#define LLVM_LIBC_SRC___SUPPORT_BUILTIN_WRAPPERS_H
 
 #include "named_pair.h"
 #include "src/__support/CPP/type_traits.h"
@@ -223,4 +223,4 @@ sub_with_borrow<unsigned long long>(unsigned long long a, unsigned long long b,
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_BUILTIN_WRAPPERS_H
+#endif // LLVM_LIBC_SRC___SUPPORT_BUILTIN_WRAPPERS_H
diff --git a/libc/src/__support/c_string.h b/libc/src/__support/c_string.h
index eaac4e7ad61d4..580a685849a6d 100644
--- a/libc/src/__support/c_string.h
+++ b/libc/src/__support/c_string.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_C_STRING_H
-#define LLVM_LIBC_SRC_SUPPORT_C_STRING_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_C_STRING_H
+#define LLVM_LIBC_SRC___SUPPORT_C_STRING_H
 
 #include "src/__support/CPP/string.h"
 #include "src/__support/macros/attributes.h" // for LIBC_INLINE
@@ -33,4 +33,4 @@ class CString {
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_C_STRING_H
+#endif // LLVM_LIBC_SRC___SUPPORT_C_STRING_H
diff --git a/libc/src/__support/char_vector.h b/libc/src/__support/char_vector.h
index e60f9fe555fff..49609fd6a2b4a 100644
--- a/libc/src/__support/char_vector.h
+++ b/libc/src/__support/char_vector.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_CHARVECTOR_H
-#define LLVM_LIBC_SRC_SUPPORT_CHARVECTOR_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CHARVECTOR_H
+#define LLVM_LIBC_SRC___SUPPORT_CHARVECTOR_H
 
 #include "src/__support/common.h"
 
@@ -75,4 +75,4 @@ class CharVector {
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_CHARVECTOR_H
+#endif // LLVM_LIBC_SRC___SUPPORT_CHARVECTOR_H
diff --git a/libc/src/__support/common.h b/libc/src/__support/common.h
index a6aaa4eb2c228..2b253fd567c19 100644
--- a/libc/src/__support/common.h
+++ b/libc/src/__support/common.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SUPPORT_COMMON_H
-#define LLVM_LIBC_SUPPORT_COMMON_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_COMMON_H
+#define LLVM_LIBC_SRC___SUPPORT_COMMON_H
 
 #ifndef LIBC_NAMESPACE
 #error "LIBC_NAMESPACE macro is not defined."
@@ -58,4 +58,4 @@ LIBC_INLINE constexpr bool same_string(char const *lhs, char const *rhs) {
       LLVM_LIBC_IS_DEFINED__EVAL_AND_STRINGIZE(macro), #macro)
 #define LLVM_LIBC_IS_DEFINED__EVAL_AND_STRINGIZE(s) #s
 
-#endif // LLVM_LIBC_SUPPORT_COMMON_H
+#endif // LLVM_LIBC_SRC___SUPPORT_COMMON_H
diff --git a/libc/src/__support/ctype_utils.h b/libc/src/__support/ctype_utils.h
index 2728146635379..61a5fe6543194 100644
--- a/libc/src/__support/ctype_utils.h
+++ b/libc/src/__support/ctype_utils.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_CTYPE_UTILS_H
-#define LLVM_LIBC_SRC_SUPPORT_CTYPE_UTILS_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_CTYPE_UTILS_H
+#define LLVM_LIBC_SRC___SUPPORT_CTYPE_UTILS_H
 
 #include "src/__support/macros/attributes.h"
 
@@ -57,4 +57,4 @@ LIBC_INLINE static constexpr int tolower(int ch) {
 } // namespace internal
 } // namespace __llvm_libc
 
-#endif //  LLVM_LIBC_SRC_SUPPORT_CTYPE_UTILS_H
+#endif //  LLVM_LIBC_SRC___SUPPORT_CTYPE_UTILS_H
diff --git a/libc/src/__support/detailed_powers_of_ten.h b/libc/src/__support/detailed_powers_of_ten.h
index 767b7cf6a65ee..5335f0dba4164 100644
--- a/libc/src/__support/detailed_powers_of_ten.h
+++ b/libc/src/__support/detailed_powers_of_ten.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LIBC_SRC_SUPPORT_DETAILED_POWERS_OF_TEN_H
-#define LIBC_SRC_SUPPORT_DETAILED_POWERS_OF_TEN_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_DETAILED_POWERS_OF_TEN_H
+#define LLVM_LIBC_SRC___SUPPORT_DETAILED_POWERS_OF_TEN_H
 
 #include "src/__support/common.h"
 
@@ -735,4 +735,4 @@ static constexpr uint64_t DETAILED_POWERS_OF_TEN[696][2] = {
 } // namespace internal
 } // namespace __llvm_libc
 
-#endif // LIBC_SRC_SUPPORT_DETAILED_POWERS_OF_TEN_H
+#endif // LLVM_LIBC_SRC___SUPPORT_DETAILED_POWERS_OF_TEN_H
diff --git a/libc/src/__support/endian.h b/libc/src/__support/endian.h
index cc4eaa29ff347..43ddbb6850666 100644
--- a/libc/src/__support/endian.h
+++ b/libc/src/__support/endian.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_ENDIAN_H
-#define LLVM_LIBC_SRC_SUPPORT_ENDIAN_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_ENDIAN_H
+#define LLVM_LIBC_SRC___SUPPORT_ENDIAN_H
 
 #include "common.h"
 
@@ -142,4 +142,4 @@ using Endian = internal::Endian<__BYTE_ORDER__>;
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_ENDIAN_H
+#endif // LLVM_LIBC_SRC___SUPPORT_ENDIAN_H
diff --git a/libc/src/__support/error_or.h b/libc/src/__support/error_or.h
index 7d1f82aeb2e01..33bb942d9d0d0 100644
--- a/libc/src/__support/error_or.h
+++ b/libc/src/__support/error_or.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SUPPORT_ERROR_OR_RESULT_H
-#define LLVM_LIBC_SUPPORT_ERROR_OR_RESULT_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_ERROR_OR_H
+#define LLVM_LIBC_SRC___SUPPORT_ERROR_OR_H
 
 #include "src/__support/CPP/expected.h"
 
@@ -36,4 +36,4 @@ using Error = cpp::unexpected<int>;
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SUPPORT_ERROR_OR_RESULT_H
+#endif // LLVM_LIBC_SRC___SUPPORT_ERROR_OR_H
diff --git a/libc/src/__support/fixedvector.h b/libc/src/__support/fixedvector.h
index 9e36a9e10b272..5dfda1e629623 100644
--- a/libc/src/__support/fixedvector.h
+++ b/libc/src/__support/fixedvector.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SUPPORT_FIXEDVECTOR_H
-#define LLVM_LIBC_SUPPORT_FIXEDVECTOR_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_FIXEDVECTOR_H
+#define LLVM_LIBC_SRC___SUPPORT_FIXEDVECTOR_H
 
 #include "src/__support/CPP/array.h"
 
@@ -59,4 +59,4 @@ template <typename T, size_t CAPACITY> class FixedVector {
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SUPPORT_FIXEDVECTOR_H
+#endif // LLVM_LIBC_SRC___SUPPORT_FIXEDVECTOR_H
diff --git a/libc/src/__support/float_to_string.h b/libc/src/__support/float_to_string.h
index 4714068eadf0e..1e78bcb200b8c 100644
--- a/libc/src/__support/float_to_string.h
+++ b/libc/src/__support/float_to_string.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_FLOAT_TO_STRING_H
-#define LLVM_LIBC_SRC_SUPPORT_FLOAT_TO_STRING_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_FLOAT_TO_STRING_H
+#define LLVM_LIBC_SRC___SUPPORT_FLOAT_TO_STRING_H
 
 #include <stdint.h>
 
@@ -756,4 +756,4 @@ FloatToString<long double>::get_negative_block(int block_index) {
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_FLOAT_TO_STRING_H
+#endif // LLVM_LIBC_SRC___SUPPORT_FLOAT_TO_STRING_H
diff --git a/libc/src/__support/high_precision_decimal.h b/libc/src/__support/high_precision_decimal.h
index 486e289f4ce61..9ee7c1fb8653f 100644
--- a/libc/src/__support/high_precision_decimal.h
+++ b/libc/src/__support/high_precision_decimal.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LIBC_SRC_SUPPORT_HIGH_PRECISION_DECIMAL_H
-#define LIBC_SRC_SUPPORT_HIGH_PRECISION_DECIMAL_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_HIGH_PRECISION_DECIMAL_H
+#define LLVM_LIBC_SRC___SUPPORT_HIGH_PRECISION_DECIMAL_H
 
 #include "src/__support/ctype_utils.h"
 #include "src/__support/str_to_integer.h"
@@ -413,4 +413,4 @@ class HighPrecisionDecimal {
 } // namespace internal
 } // namespace __llvm_libc
 
-#endif // LIBC_SRC_SUPPORT_HIGH_PRECISION_DECIMAL_H
+#endif // LLVM_LIBC_SRC___SUPPORT_HIGH_PRECISION_DECIMAL_H
diff --git a/libc/src/__support/integer_operations.h b/libc/src/__support/integer_operations.h
index 22c1683684464..396ebc7cbb9db 100644
--- a/libc/src/__support/integer_operations.h
+++ b/libc/src/__support/integer_operations.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_STDLIB_ABS_UTILS_H
-#define LLVM_LIBC_SRC_STDLIB_ABS_UTILS_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_INTEGER_OPERATIONS_H
+#define LLVM_LIBC_SRC___SUPPORT_INTEGER_OPERATIONS_H
 
 #include "src/__support/CPP/type_traits.h"
 
@@ -27,4 +27,4 @@ integer_rem_quo(T x, T y, T &quot, T &rem) {
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_STDLIB_ABS_UTILS_H
+#endif // LLVM_LIBC_SRC___SUPPORT_INTEGER_OPERATIONS_H
diff --git a/libc/src/__support/integer_to_string.h b/libc/src/__support/integer_to_string.h
index 0ed7c6bcc6c0a..2c11d834a8f34 100644
--- a/libc/src/__support/integer_to_string.h
+++ b/libc/src/__support/integer_to_string.h
@@ -54,8 +54,8 @@
 //   IntegerToString<uint8_t, radix::Hex::WithWidth<4>::Uppercase>(255) : "00FF"
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_INTEGER_TO_STRING_H
-#define LLVM_LIBC_SRC_SUPPORT_INTEGER_TO_STRING_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_INTEGER_TO_STRING_H
+#define LLVM_LIBC_SRC___SUPPORT_INTEGER_TO_STRING_H
 
 #include <stdint.h>
 
@@ -318,4 +318,4 @@ template <typename T, typename Fmt = radix::Dec> class IntegerToString {
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_INTEGER_TO_STRING_H
+#endif // LLVM_LIBC_SRC___SUPPORT_INTEGER_TO_STRING_H
diff --git a/libc/src/__support/integer_utils.h b/libc/src/__support/integer_utils.h
index aedcd353436f9..9a734da3e117b 100644
--- a/libc/src/__support/integer_utils.h
+++ b/libc/src/__support/integer_utils.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_INTEGER_UTILS_H
-#define LLVM_LIBC_SRC_SUPPORT_INTEGER_UTILS_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_INTEGER_UTILS_H
+#define LLVM_LIBC_SRC___SUPPORT_INTEGER_UTILS_H
 
 #include "src/__support/CPP/type_traits.h"
 #include "src/__support/common.h"
@@ -62,4 +62,4 @@ LIBC_INLINE NumberPair<uint64_t> full_mul<uint64_t>(uint64_t a, uint64_t b) {
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_INTEGER_UTILS_H
+#endif // LLVM_LIBC_SRC___SUPPORT_INTEGER_UTILS_H
diff --git a/libc/src/__support/libc_assert.h b/libc/src/__support/libc_assert.h
index 8c1f630fb4a40..4190cfe04a759 100644
--- a/libc/src/__support/libc_assert.h
+++ b/libc/src/__support/libc_assert.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_LIBC_ASSERT_H
-#define LLVM_LIBC_SRC_SUPPORT_LIBC_ASSERT_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_LIBC_ASSERT_H
+#define LLVM_LIBC_SRC___SUPPORT_LIBC_ASSERT_H
 
 #ifdef LIBC_COPT_USE_C_ASSERT
 
@@ -83,4 +83,4 @@ LIBC_INLINE void report_assertion_failure(const char *assertion,
 
 #endif // LIBC_COPT_USE_C_ASSERT
 
-#endif // LLVM_LIBC_SRC_SUPPORT_LIBC_ASSERT_H
+#endif // LLVM_LIBC_SRC___SUPPORT_LIBC_ASSERT_H
diff --git a/libc/src/__support/macros/attributes.h b/libc/src/__support/macros/attributes.h
index 0c8a37b34e66a..8637e165fe3bc 100644
--- a/libc/src/__support/macros/attributes.h
+++ b/libc/src/__support/macros/attributes.h
@@ -14,8 +14,8 @@
 // Most macros here are exposing GCC or Clang features, and are stubbed out for
 // other compilers.
 
-#ifndef LLVM_LIBC_SUPPORT_MACROS_ATTRIBUTES_H
-#define LLVM_LIBC_SUPPORT_MACROS_ATTRIBUTES_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_MACROS_ATTRIBUTES_H
+#define LLVM_LIBC_SRC___SUPPORT_MACROS_ATTRIBUTES_H
 
 #include "properties/architectures.h"
 
@@ -30,4 +30,4 @@
 #define LIBC_THREAD_LOCAL thread_local
 #endif
 
-#endif // LLVM_LIBC_SUPPORT_MACROS_ATTRIBUTES_H
+#endif // LLVM_LIBC_SRC___SUPPORT_MACROS_ATTRIBUTES_H
diff --git a/libc/src/__support/macros/config.h b/libc/src/__support/macros/config.h
index 43e81363c1b20..fcc8f551a783f 100644
--- a/libc/src/__support/macros/config.h
+++ b/libc/src/__support/macros/config.h
@@ -10,8 +10,8 @@
 // produce portable code by parameterizing compilation based on the presence or
 // lack of a given feature.
 
-#ifndef LLVM_LIBC_SUPPORT_MACROS_CONFIG_H
-#define LLVM_LIBC_SUPPORT_MACROS_CONFIG_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_MACROS_CONFIG_H
+#define LLVM_LIBC_SRC___SUPPORT_MACROS_CONFIG_H
 
 // LIBC_HAS_BUILTIN()
 //
@@ -47,4 +47,4 @@
 #define LIBC_HAS_ATTRIBUTE(f) 0
 #endif
 
-#endif // LLVM_LIBC_SUPPORT_MACROS_CONFIG_H
+#endif // LLVM_LIBC_SRC___SUPPORT_MACROS_CONFIG_H
diff --git a/libc/src/__support/macros/optimization.h b/libc/src/__support/macros/optimization.h
index ba4441090cde5..1d221ff6aff45 100644
--- a/libc/src/__support/macros/optimization.h
+++ b/libc/src/__support/macros/optimization.h
@@ -7,8 +7,8 @@
 //===----------------------------------------------------------------------===//
 // This header file defines portable macros for performance optimization.
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_MACROS_OPTIMIZATION_H
-#define LLVM_LIBC_SRC_SUPPORT_MACROS_OPTIMIZATION_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_MACROS_OPTIMIZATION_H
+#define LLVM_LIBC_SRC___SUPPORT_MACROS_OPTIMIZATION_H
 
 #include "src/__support/macros/attributes.h"          // LIBC_INLINE
 #include "src/__support/macros/config.h"              // LIBC_HAS_BUILTIN
@@ -33,4 +33,4 @@ LIBC_INLINE constexpr bool expects_bool_condition(T value, T expected) {
 #error "Unhandled compiler"
 #endif
 
-#endif /* LLVM_LIBC_SRC_SUPPORT_MACROS_OPTIMIZATION_H */
+#endif // LLVM_LIBC_SRC___SUPPORT_MACROS_OPTIMIZATION_H
diff --git a/libc/src/__support/macros/properties/architectures.h b/libc/src/__support/macros/properties/architectures.h
index 79bf5442f0e81..2ece9c5728d6d 100644
--- a/libc/src/__support/macros/properties/architectures.h
+++ b/libc/src/__support/macros/properties/architectures.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SUPPORT_MACROS_PROPERTIES_ARCHITECTURES_H
-#define LLVM_LIBC_SUPPORT_MACROS_PROPERTIES_ARCHITECTURES_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_MACROS_PROPERTIES_ARCHITECTURES_H
+#define LLVM_LIBC_SRC___SUPPORT_MACROS_PROPERTIES_ARCHITECTURES_H
 
 #if defined(__AMDGPU__)
 #define LIBC_TARGET_ARCH_IS_AMDGPU
@@ -62,4 +62,4 @@
 #define LIBC_TARGET_ARCH_IS_ANY_RISCV
 #endif
 
-#endif // LLVM_LIBC_SUPPORT_MACROS_PROPERTIES_ARCHITECTURES_H
+#endif // LLVM_LIBC_SRC___SUPPORT_MACROS_PROPERTIES_ARCHITECTURES_H
diff --git a/libc/src/__support/macros/properties/compiler.h b/libc/src/__support/macros/properties/compiler.h
index 54bcf84d927b1..a7a2822bf6a14 100644
--- a/libc/src/__support/macros/properties/compiler.h
+++ b/libc/src/__support/macros/properties/compiler.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SUPPORT_MACROS_PROPERTIES_COMPILER_H
-#define LLVM_LIBC_SUPPORT_MACROS_PROPERTIES_COMPILER_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_MACROS_PROPERTIES_COMPILER_H
+#define LLVM_LIBC_SRC___SUPPORT_MACROS_PROPERTIES_COMPILER_H
 
 #if defined(__clang__)
 #define LIBC_COMPILER_IS_CLANG
@@ -21,4 +21,4 @@
 #define LIBC_COMPILER_IS_MSC
 #endif
 
-#endif // LLVM_LIBC_SUPPORT_MACROS_PROPERTIES_COMPILER_H
+#endif // LLVM_LIBC_SRC___SUPPORT_MACROS_PROPERTIES_COMPILER_H
diff --git a/libc/src/__support/macros/properties/cpu_features.h b/libc/src/__support/macros/properties/cpu_features.h
index 493d9f446d374..80d48be702070 100644
--- a/libc/src/__support/macros/properties/cpu_features.h
+++ b/libc/src/__support/macros/properties/cpu_features.h
@@ -9,8 +9,8 @@
 // preprocessor definitions.
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_MACROS_PROPERTIES_CPU_FEATURES_H
-#define LLVM_LIBC_SRC_SUPPORT_MACROS_PROPERTIES_CPU_FEATURES_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_MACROS_PROPERTIES_CPU_FEATURES_H
+#define LLVM_LIBC_SRC___SUPPORT_MACROS_PROPERTIES_CPU_FEATURES_H
 
 #include "architectures.h"
 
@@ -49,4 +49,4 @@
 #define LIBC_TARGET_CPU_HAS_NEAREST_INT
 #endif
 
-#endif // LLVM_LIBC_SRC_SUPPORT_MACROS_PROPERTIES_CPU_FEATURES_H
+#endif // LLVM_LIBC_SRC___SUPPORT_MACROS_PROPERTIES_CPU_FEATURES_H
diff --git a/libc/src/__support/macros/sanitizer.h b/libc/src/__support/macros/sanitizer.h
index fb1f1440a34d4..6989672b4839d 100644
--- a/libc/src/__support/macros/sanitizer.h
+++ b/libc/src/__support/macros/sanitizer.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_MACROS_SANITIZER_H
-#define LLVM_LIBC_SRC_SUPPORT_MACROS_SANITIZER_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_MACROS_SANITIZER_H
+#define LLVM_LIBC_SRC___SUPPORT_MACROS_SANITIZER_H
 
 #include "src/__support/macros/config.h" //LIBC_HAS_FEATURE
 
@@ -65,4 +65,4 @@
 #define ASAN_UNPOISON_MEMORY_REGION(addr, size) ((void)(addr), (void)(size))
 #endif
 
-#endif // LLVM_LIBC_SRC_SUPPORT_MACROS_SANITIZER_H
+#endif // LLVM_LIBC_SRC___SUPPORT_MACROS_SANITIZER_H
diff --git a/libc/src/__support/named_pair.h b/libc/src/__support/named_pair.h
index a27a98ab03337..bd7dccf9810c7 100644
--- a/libc/src/__support/named_pair.h
+++ b/libc/src/__support/named_pair.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_NAMED_PAIR_H
-#define LLVM_LIBC_SRC_SUPPORT_NAMED_PAIR_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_NAMED_PAIR_H
+#define LLVM_LIBC_SRC___SUPPORT_NAMED_PAIR_H
 
 #define DEFINE_NAMED_PAIR_TEMPLATE(Name, FirstField, SecondField)              \
   template <typename T1, typename T2 = T1> struct Name {                       \
@@ -15,4 +15,4 @@
     T2 SecondField;                                                            \
   }
 
-#endif // LLVM_LIBC_SRC_SUPPORT_NAMED_PAIR_H
+#endif // LLVM_LIBC_SRC___SUPPORT_NAMED_PAIR_H
diff --git a/libc/src/__support/number_pair.h b/libc/src/__support/number_pair.h
index dc875d3141574..3f23394ee4cc2 100644
--- a/libc/src/__support/number_pair.h
+++ b/libc/src/__support/number_pair.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_NUMBER_PAIR_H
-#define LLVM_LIBC_SRC_SUPPORT_NUMBER_PAIR_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_NUMBER_PAIR_H
+#define LLVM_LIBC_SRC___SUPPORT_NUMBER_PAIR_H
 
 #include "CPP/type_traits.h"
 #include "named_pair.h"
@@ -31,4 +31,4 @@ split(T a) {
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_NUMBER_PAIR_H
+#endif // LLVM_LIBC_SRC___SUPPORT_NUMBER_PAIR_H
diff --git a/libc/src/__support/ryu_constants.h b/libc/src/__support/ryu_constants.h
index 9858aacba6cba..1ecb34e661ba8 100644
--- a/libc/src/__support/ryu_constants.h
+++ b/libc/src/__support/ryu_constants.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_RYU_CONSTANTS_H
-#define LLVM_LIBC_SRC_SUPPORT_RYU_CONSTANTS_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_RYU_CONSTANTS_H
+#define LLVM_LIBC_SRC___SUPPORT_RYU_CONSTANTS_H
 
 #include <stddef.h>
 #include <stdint.h>
@@ -4401,4 +4401,4 @@ constexpr uint64_t POW10_SPLIT_2[3133][3] = {
     {0u, 0u, 33000000000u},
 };
 
-#endif // LLVM_LIBC_SRC_SUPPORT_RYU_CONSTANTS_H
+#endif // LLVM_LIBC_SRC___SUPPORT_RYU_CONSTANTS_H
diff --git a/libc/src/__support/ryu_long_double_constants.h b/libc/src/__support/ryu_long_double_constants.h
index 8415423e9eddd..7c5297d9134bb 100644
--- a/libc/src/__support/ryu_long_double_constants.h
+++ b/libc/src/__support/ryu_long_double_constants.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_RYU_LONG_DOUBLE_CONSTANTS_H
-#define LLVM_LIBC_SRC_SUPPORT_RYU_LONG_DOUBLE_CONSTANTS_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_RYU_LONG_DOUBLE_CONSTANTS_H
+#define LLVM_LIBC_SRC___SUPPORT_RYU_LONG_DOUBLE_CONSTANTS_H
 
 #include <stddef.h>
 #include <stdint.h>
@@ -119923,4 +119923,4 @@ constexpr uint64_t POW10_SPLIT_2[][5] = {
     {0u, 0u, 0u, 16717361816799281152u, 3479003u},
 };
 
-#endif // LLVM_LIBC_SRC_SUPPORT_RYU_LONG_DOUBLE_CONSTANTS_H
+#endif // LLVM_LIBC_SRC___SUPPORT_RYU_LONG_DOUBLE_CONSTANTS_H
diff --git a/libc/src/__support/str_to_float.h b/libc/src/__support/str_to_float.h
index 813405ef2f036..58bdee2c573b5 100644
--- a/libc/src/__support/str_to_float.h
+++ b/libc/src/__support/str_to_float.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LIBC_SRC_SUPPORT_STR_TO_FLOAT_H
-#define LIBC_SRC_SUPPORT_STR_TO_FLOAT_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_STR_TO_FLOAT_H
+#define LLVM_LIBC_SRC___SUPPORT_STR_TO_FLOAT_H
 
 #include "src/__support/CPP/limits.h"
 #include "src/__support/CPP/optional.h"
@@ -1249,4 +1249,4 @@ LIBC_INLINE StrToNumResult<T> strtofloatingpoint(const char *__restrict src) {
 } // namespace internal
 } // namespace __llvm_libc
 
-#endif // LIBC_SRC_SUPPORT_STR_TO_FLOAT_H
+#endif // LLVM_LIBC_SRC___SUPPORT_STR_TO_FLOAT_H
diff --git a/libc/src/__support/str_to_integer.h b/libc/src/__support/str_to_integer.h
index fd872177c68b6..f9608928430a8 100644
--- a/libc/src/__support/str_to_integer.h
+++ b/libc/src/__support/str_to_integer.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LIBC_SRC_SUPPORT_STR_TO_INTEGER_H
-#define LIBC_SRC_SUPPORT_STR_TO_INTEGER_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_STR_TO_INTEGER_H
+#define LLVM_LIBC_SRC___SUPPORT_STR_TO_INTEGER_H
 
 #include "src/__support/CPP/limits.h"
 #include "src/__support/CPP/type_traits.h"
@@ -152,4 +152,4 @@ LIBC_INLINE StrToNumResult<T> strtointeger(const char *__restrict src,
 } // namespace internal
 } // namespace __llvm_libc
 
-#endif // LIBC_SRC_SUPPORT_STR_TO_INTEGER_H
+#endif // LLVM_LIBC_SRC___SUPPORT_STR_TO_INTEGER_H
diff --git a/libc/src/__support/str_to_num_result.h b/libc/src/__support/str_to_num_result.h
index cd0e24f6112d2..ea96f950cfb99 100644
--- a/libc/src/__support/str_to_num_result.h
+++ b/libc/src/__support/str_to_num_result.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SUPPORT_STR_TO_NUM_RESULT_H
-#define LLVM_LIBC_SUPPORT_STR_TO_NUM_RESULT_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_STR_TO_NUM_RESULT_H
+#define LLVM_LIBC_SRC___SUPPORT_STR_TO_NUM_RESULT_H
 
 #include <stddef.h>
 
@@ -30,4 +30,4 @@ template <typename T> struct StrToNumResult {
 };
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SUPPORT_STR_TO_NUM_RESULT_H
+#endif // LLVM_LIBC_SRC___SUPPORT_STR_TO_NUM_RESULT_H
diff --git a/libc/src/__support/threads/callonce.h b/libc/src/__support/threads/callonce.h
index 4ffff2a2c71a6..12e5c82a89d48 100644
--- a/libc/src/__support/threads/callonce.h
+++ b/libc/src/__support/threads/callonce.h
@@ -6,6 +6,9 @@
 //
 //===----------------------------------------------------------------------===//
 
+#ifndef LLVM_LIBC_SRC___SUPPORT_THREADS_CALLONCE_H
+#define LLVM_LIBC_SRC___SUPPORT_THREADS_CALLONCE_H
+
 namespace __llvm_libc {
 
 struct CallOnceFlag;
@@ -14,3 +17,5 @@ using CallOnceCallback = void(void);
 int callonce(CallOnceFlag *flag, CallOnceCallback *callback);
 
 } // namespace __llvm_libc
+
+#endif // LLVM_LIBC_SRC___SUPPORT_THREADS_CALLONCE_H
diff --git a/libc/src/__support/threads/fork_callbacks.h b/libc/src/__support/threads/fork_callbacks.h
index 566290a788155..5e77c35f6b5a8 100644
--- a/libc/src/__support/threads/fork_callbacks.h
+++ b/libc/src/__support/threads/fork_callbacks.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_THREAD_FORK_CALLBACKS_H
-#define LLVM_LIBC_SRC_SUPPORT_THREAD_FORK_CALLBACKS_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_THREADS_FORK_CALLBACKS_H
+#define LLVM_LIBC_SRC___SUPPORT_THREADS_FORK_CALLBACKS_H
 
 namespace __llvm_libc {
 
@@ -21,4 +21,4 @@ void invoke_child_callbacks();
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_THREAD_FORK_CALLBACKS_H
+#endif // LLVM_LIBC_SRC___SUPPORT_THREADS_FORK_CALLBACKS_H
diff --git a/libc/src/__support/threads/gpu/mutex.h b/libc/src/__support/threads/gpu/mutex.h
index c4a75907eed7c..5a5dc73e2515a 100644
--- a/libc/src/__support/threads/gpu/mutex.h
+++ b/libc/src/__support/threads/gpu/mutex.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_THREAD_GPU_MUTEX_H
-#define LLVM_LIBC_SRC_SUPPORT_THREAD_GPU_MUTEX_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_THREAD_GPU_MUTEX_H
+#define LLVM_LIBC_SRC___SUPPORT_THREAD_GPU_MUTEX_H
 
 #include "src/__support/macros/attributes.h"
 #include "src/__support/threads/mutex_common.h"
diff --git a/libc/src/__support/threads/linux/futex_word.h b/libc/src/__support/threads/linux/futex_word.h
index dc9af96f0a667..4585aacf4623a 100644
--- a/libc/src/__support/threads/linux/futex_word.h
+++ b/libc/src/__support/threads/linux/futex_word.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_THREADS_LINUX_FUTEX_WORD_H
-#define LLVM_LIBC_SRC_SUPPORT_THREADS_LINUX_FUTEX_WORD_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_THREADS_LINUX_FUTEX_WORD_H
+#define LLVM_LIBC_SRC___SUPPORT_THREADS_LINUX_FUTEX_WORD_H
 
 #include <stdint.h>
 #include <sys/syscall.h>
@@ -27,4 +27,4 @@ constexpr auto FUTEX_SYSCALL_ID = SYS_futex_time64;
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_THREADS_LINUX_FUTEX_WORD_H
+#endif // LLVM_LIBC_SRC___SUPPORT_THREADS_LINUX_FUTEX_WORD_H
diff --git a/libc/src/__support/threads/linux/mutex.h b/libc/src/__support/threads/linux/mutex.h
index 362f8b4b5d1f2..9b22fbab7c4c3 100644
--- a/libc/src/__support/threads/linux/mutex.h
+++ b/libc/src/__support/threads/linux/mutex.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_THREAD_LINUX_MUTEX_H
-#define LLVM_LIBC_SRC_SUPPORT_THREAD_LINUX_MUTEX_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_THREADS_LINUX_MUTEX_H
+#define LLVM_LIBC_SRC___SUPPORT_THREADS_LINUX_MUTEX_H
 
 #include "src/__support/CPP/atomic.h"
 #include "src/__support/OSUtil/syscall.h" // For syscall functions.
@@ -133,4 +133,4 @@ struct Mutex {
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_THREAD_LINUX_MUTEX_H
+#endif // LLVM_LIBC_SRC___SUPPORT_THREADS_LINUX_MUTEX_H
diff --git a/libc/src/__support/threads/mutex.h b/libc/src/__support/threads/mutex.h
index 9f73d7c7409bf..7b27514c748b9 100644
--- a/libc/src/__support/threads/mutex.h
+++ b/libc/src/__support/threads/mutex.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_THREAD_MUTEX_H
-#define LLVM_LIBC_SRC_SUPPORT_THREAD_MUTEX_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_THREADS_MUTEX_H
+#define LLVM_LIBC_SRC___SUPPORT_THREADS_MUTEX_H
 
 #include "src/__support/macros/properties/architectures.h"
 
@@ -57,4 +57,4 @@ class MutexLock {
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_THREAD_MUTEX_H
+#endif // LLVM_LIBC_SRC___SUPPORT_THREADS_MUTEX_H
diff --git a/libc/src/__support/threads/mutex_common.h b/libc/src/__support/threads/mutex_common.h
index 2fde20a3fe828..ec275eb2b1c4e 100644
--- a/libc/src/__support/threads/mutex_common.h
+++ b/libc/src/__support/threads/mutex_common.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_THREAD_MUTEX_COMMON_H
-#define LLVM_LIBC_SRC_SUPPORT_THREAD_MUTEX_COMMON_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_THREADS_MUTEX_COMMON_H
+#define LLVM_LIBC_SRC___SUPPORT_THREADS_MUTEX_COMMON_H
 
 namespace __llvm_libc {
 
@@ -21,4 +21,4 @@ enum class MutexError : int {
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_THREAD_MUTEX_COMMON_H
+#endif // LLVM_LIBC_SRC___SUPPORT_THREADS_MUTEX_COMMON_H
diff --git a/libc/src/__support/threads/thread.h b/libc/src/__support/threads/thread.h
index 0c889096741ff..6fbacef483d35 100644
--- a/libc/src/__support/threads/thread.h
+++ b/libc/src/__support/threads/thread.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_THREADS_THREAD_H
-#define LLVM_LIBC_SRC_SUPPORT_THREADS_THREAD_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_THREADS_THREAD_H
+#define LLVM_LIBC_SRC___SUPPORT_THREADS_THREAD_H
 
 #include "src/__support/CPP/atomic.h"
 #include "src/__support/CPP/optional.h"
@@ -249,4 +249,4 @@ void call_atexit_callbacks(ThreadAttributes *attrib);
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_THREADS_THREAD_H
+#endif // LLVM_LIBC_SRC___SUPPORT_THREADS_THREAD_H
diff --git a/libc/src/__support/wctype_utils.h b/libc/src/__support/wctype_utils.h
index 7e11b2d8b1725..d8de9fd806087 100644
--- a/libc/src/__support/wctype_utils.h
+++ b/libc/src/__support/wctype_utils.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SUPPORT_WCTYPE_UTILS_H
-#define LLVM_LIBC_SRC_SUPPORT_WCTYPE_UTILS_H
+#ifndef LLVM_LIBC_SRC___SUPPORT_WCTYPE_UTILS_H
+#define LLVM_LIBC_SRC___SUPPORT_WCTYPE_UTILS_H
 
 #include "src/__support/CPP/optional.h"
 #include "src/__support/macros/attributes.h" // LIBC_INLINE
@@ -42,4 +42,4 @@ LIBC_INLINE cpp::optional<wint_t> btowc(int c) {
 } // namespace internal
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SUPPORT_WCTYPE_UTILS_H
+#endif // LLVM_LIBC_SRC___SUPPORT_WCTYPE_UTILS_H
diff --git a/libc/src/assert/__assert_fail.h b/libc/src/assert/__assert_fail.h
index 3ad240049876c..ba8db9d47ba35 100644
--- a/libc/src/assert/__assert_fail.h
+++ b/libc/src/assert/__assert_fail.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_ASSERT_ASSERT_FAIL_H
-#define LLVM_LIBC_SRC_ASSERT_ASSERT_FAIL_H
+#ifndef LLVM_LIBC_SRC_ASSERT___ASSERT_FAIL_H
+#define LLVM_LIBC_SRC_ASSERT___ASSERT_FAIL_H
 
 #include <stddef.h>
 
@@ -18,4 +18,4 @@ namespace __llvm_libc {
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_ASSERT_ASSERT_FAIL_H
+#endif // LLVM_LIBC_SRC_ASSERT___ASSERT_FAIL_H
diff --git a/libc/src/errno/libc_errno.h b/libc/src/errno/libc_errno.h
index 8007f0dea58b1..c81ea3129333a 100644
--- a/libc/src/errno/libc_errno.h
+++ b/libc/src/errno/libc_errno.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_ERRNO_LLVMLIBC_ERRNO_H
-#define LLVM_LIBC_SRC_ERRNO_LLVMLIBC_ERRNO_H
+#ifndef LLVM_LIBC_SRC_ERRNO_LIBC_ERRNO_H
+#define LLVM_LIBC_SRC_ERRNO_LIBC_ERRNO_H
 
 #include "src/__support/macros/attributes.h"
 #include "src/__support/macros/properties/architectures.h"
@@ -53,4 +53,4 @@ extern "C" LIBC_THREAD_LOCAL int __llvmlibc_internal_errno;
 } // namespace __llvm_libc
 #endif
 
-#endif // LLVM_LIBC_SRC_ERRNO_LLVMLIBC_ERRNO_H
+#endif // LLVM_LIBC_SRC_ERRNO_LIBC_ERRNO_H
diff --git a/libc/src/math/generic/math_utils.h b/libc/src/math/generic/math_utils.h
index 0399f7d0adfff..f286c9ce9faed 100644
--- a/libc/src/math/generic/math_utils.h
+++ b/libc/src/math/generic/math_utils.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_MATH_MATH_UTILS_H
-#define LLVM_LIBC_SRC_MATH_MATH_UTILS_H
+#ifndef LLVM_LIBC_SRC_MATH_GENERIC_MATH_UTILS_H
+#define LLVM_LIBC_SRC_MATH_GENERIC_MATH_UTILS_H
 
 #include "src/__support/CPP/bit.h"
 #include "src/__support/CPP/type_traits.h"
@@ -104,4 +104,4 @@ LIBC_INLINE constexpr float invalid(T x) {
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_MATH_MATH_UTILS_H
+#endif // LLVM_LIBC_SRC_MATH_GENERIC_MATH_UTILS_H
diff --git a/libc/src/math/generic/sincosf_utils.h b/libc/src/math/generic/sincosf_utils.h
index f23617ebf180c..2488f50720896 100644
--- a/libc/src/math/generic/sincosf_utils.h
+++ b/libc/src/math/generic/sincosf_utils.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_MATH_SINCOSF_UTILS_H
-#define LLVM_LIBC_SRC_MATH_SINCOSF_UTILS_H
+#ifndef LLVM_LIBC_SRC_MATH_GENERIC_SINCOSF_UTILS_H
+#define LLVM_LIBC_SRC_MATH_GENERIC_SINCOSF_UTILS_H
 
 #include "src/__support/FPUtil/FPBits.h"
 #include "src/__support/FPUtil/PolyEval.h"
@@ -97,4 +97,4 @@ LIBC_INLINE void sincosf_eval(double xd, uint32_t x_abs, double &sin_k,
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_MATH_SINCOSF_UTILS_H
+#endif // LLVM_LIBC_SRC_MATH_GENERIC_SINCOSF_UTILS_H
diff --git a/libc/src/math/ldexpl.h b/libc/src/math/ldexpl.h
index bf8435b1a21d8..3ee9c045e1713 100644
--- a/libc/src/math/ldexpl.h
+++ b/libc/src/math/ldexpl.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_MATH_ldexpl_H
-#define LLVM_LIBC_SRC_MATH_ldexpl_H
+#ifndef LLVM_LIBC_SRC_MATH_LDEXPL_H
+#define LLVM_LIBC_SRC_MATH_LDEXPL_H
 
 namespace __llvm_libc {
 
@@ -15,4 +15,4 @@ long double ldexpl(long double x, int exp);
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_MATH_ldexpl_H
+#endif // LLVM_LIBC_SRC_MATH_LDEXPL_H
diff --git a/libc/src/pthread/pthread_atfork.h b/libc/src/pthread/pthread_atfork.h
index 500478b2c5076..bd8bc8a35ef03 100644
--- a/libc/src/pthread/pthread_atfork.h
+++ b/libc/src/pthread/pthread_atfork.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_THREADS_PTHREAD_ATFORK_H
-#define LLVM_LIBC_SRC_THREADS_PTHREAD_ATFORK_H
+#ifndef LLVM_LIBC_SRC_PTHREAD_PTHREAD_ATFORK_H
+#define LLVM_LIBC_SRC_PTHREAD_PTHREAD_ATFORK_H
 
 #include <pthread.h>
 
@@ -18,4 +18,4 @@ int pthread_atfork(__atfork_callback_t prepare, __atfork_callback_t parent,
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_THREADS_PTHREAD_ATFORK_H
+#endif // LLVM_LIBC_SRC_PTHREAD_PTHREAD_ATFORK_H
diff --git a/libc/src/pthread/pthread_create.h b/libc/src/pthread/pthread_create.h
index 500aa6cc8138e..6df6c9559ea94 100644
--- a/libc/src/pthread/pthread_create.h
+++ b/libc/src/pthread/pthread_create.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_THREADS_PTHREAD_CREATE_H
-#define LLVM_LIBC_SRC_THREADS_PTHREAD_CREATE_H
+#ifndef LLVM_LIBC_SRC_PTHREAD_PTHREAD_CREATE_H
+#define LLVM_LIBC_SRC_PTHREAD_PTHREAD_CREATE_H
 
 #include <pthread.h>
 
@@ -19,4 +19,4 @@ int pthread_create(pthread_t *__restrict thread,
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_THREADS_PTHREAD_CREATE_H
+#endif // LLVM_LIBC_SRC_PTHREAD_PTHREAD_CREATE_H
diff --git a/libc/src/pthread/pthread_detach.h b/libc/src/pthread/pthread_detach.h
index 2122ed6881a09..5beab40b3061a 100644
--- a/libc/src/pthread/pthread_detach.h
+++ b/libc/src/pthread/pthread_detach.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_THREADS_PTHREAD_DETACH_H
-#define LLVM_LIBC_SRC_THREADS_PTHREAD_DETACH_H
+#ifndef LLVM_LIBC_SRC_PTHREAD_PTHREAD_DETACH_H
+#define LLVM_LIBC_SRC_PTHREAD_PTHREAD_DETACH_H
 
 #include <pthread.h>
 
@@ -17,4 +17,4 @@ int pthread_detach(pthread_t thread);
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_THREADS_PTHREAD_DETACH_H
+#endif // LLVM_LIBC_SRC_PTHREAD_PTHREAD_DETACH_H
diff --git a/libc/src/pthread/pthread_equal.h b/libc/src/pthread/pthread_equal.h
index a4518d179e78c..aa5dfed54a5e0 100644
--- a/libc/src/pthread/pthread_equal.h
+++ b/libc/src/pthread/pthread_equal.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_THREADS_PTHREAD_EQUAL_H
-#define LLVM_LIBC_SRC_THREADS_PTHREAD_EQUAL_H
+#ifndef LLVM_LIBC_SRC_PTHREAD_PTHREAD_EQUAL_H
+#define LLVM_LIBC_SRC_PTHREAD_PTHREAD_EQUAL_H
 
 #include <pthread.h>
 
@@ -17,4 +17,4 @@ int pthread_equal(pthread_t lhs, pthread_t rhs);
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_THREADS_PTHREAD_EQUAL_H
+#endif // LLVM_LIBC_SRC_PTHREAD_PTHREAD_EQUAL_H
diff --git a/libc/src/pthread/pthread_exit.h b/libc/src/pthread/pthread_exit.h
index d8bdbb3f5bc69..40051d70e0e00 100644
--- a/libc/src/pthread/pthread_exit.h
+++ b/libc/src/pthread/pthread_exit.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_THREADS_PTHREAD_EXIT_H
-#define LLVM_LIBC_SRC_THREADS_PTHREAD_EXIT_H
+#ifndef LLVM_LIBC_SRC_PTHREAD_PTHREAD_EXIT_H
+#define LLVM_LIBC_SRC_PTHREAD_PTHREAD_EXIT_H
 
 #include <pthread.h>
 
@@ -17,4 +17,4 @@ namespace __llvm_libc {
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_THREADS_PTHREAD_EXIT_H
+#endif // LLVM_LIBC_SRC_PTHREAD_PTHREAD_EXIT_H
diff --git a/libc/src/pthread/pthread_join.h b/libc/src/pthread/pthread_join.h
index d659897b07377..1200fba3b20d8 100644
--- a/libc/src/pthread/pthread_join.h
+++ b/libc/src/pthread/pthread_join.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_THREADS_PTHREAD_JOIN_H
-#define LLVM_LIBC_SRC_THREADS_PTHREAD_JOIN_H
+#ifndef LLVM_LIBC_SRC_PTHREAD_PTHREAD_JOIN_H
+#define LLVM_LIBC_SRC_PTHREAD_PTHREAD_JOIN_H
 
 #include <pthread.h>
 
@@ -17,4 +17,4 @@ int pthread_join(pthread_t thread, void **retval);
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_THREADS_PTHREAD_JOIN_H
+#endif // LLVM_LIBC_SRC_PTHREAD_PTHREAD_JOIN_H
diff --git a/libc/src/pthread/pthread_mutex_destroy.h b/libc/src/pthread/pthread_mutex_destroy.h
index bd6ea1932c1b6..b6461a0da9f39 100644
--- a/libc/src/pthread/pthread_mutex_destroy.h
+++ b/libc/src/pthread/pthread_mutex_destroy.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_PTHREAD_PTHREAD_MUTEX__DESTROY_H
-#define LLVM_LIBC_SRC_PTHREAD_PTHREAD_MUTEX__DESTROY_H
+#ifndef LLVM_LIBC_SRC_PTHREAD_PTHREAD_MUTEX_DESTROY_H
+#define LLVM_LIBC_SRC_PTHREAD_PTHREAD_MUTEX_DESTROY_H
 
 #include <pthread.h>
 
diff --git a/libc/src/pthread/pthread_mutex_init.h b/libc/src/pthread/pthread_mutex_init.h
index 237ea183b8c6a..678cac32d900d 100644
--- a/libc/src/pthread/pthread_mutex_init.h
+++ b/libc/src/pthread/pthread_mutex_init.h
@@ -18,4 +18,4 @@ int pthread_mutex_init(pthread_mutex_t *mutex,
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_PTHREAD_pthread_mutex_INIT_H
+#endif // LLVM_LIBC_SRC_PTHREAD_PTHREAD_MUTEX_INIT_H
diff --git a/libc/src/pthread/pthread_mutexattr_setpshared.h b/libc/src/pthread/pthread_mutexattr_setpshared.h
index 6b03ed4a85556..21c7734e1fe1b 100644
--- a/libc/src/pthread/pthread_mutexattr_setpshared.h
+++ b/libc/src/pthread/pthread_mutexattr_setpshared.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_PTHREAD_PTHREAD_MUTEXATTR_SETpshared_H
-#define LLVM_LIBC_SRC_PTHREAD_PTHREAD_MUTEXATTR_SETpshared_H
+#ifndef LLVM_LIBC_SRC_PTHREAD_PTHREAD_MUTEXATTR_SETPSHARED_H
+#define LLVM_LIBC_SRC_PTHREAD_PTHREAD_MUTEXATTR_SETPSHARED_H
 
 #include <pthread.h>
 
@@ -18,4 +18,4 @@ int pthread_mutexattr_setpshared(pthread_mutexattr_t *__restrict attr,
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_PTHREAD_PTHREAD_MUTEXATTR_SETpshared_H
+#endif // LLVM_LIBC_SRC_PTHREAD_PTHREAD_MUTEXATTR_SETPSHARED_H
diff --git a/libc/src/pthread/pthread_once.h b/libc/src/pthread/pthread_once.h
index 35e706ebc2407..b9b7212f72af6 100644
--- a/libc/src/pthread/pthread_once.h
+++ b/libc/src/pthread/pthread_once.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_THREADS_PTHREAD_ONCE_H
-#define LLVM_LIBC_SRC_THREADS_PTHREAD_ONCE_H
+#ifndef LLVM_LIBC_SRC_PTHREAD_PTHREAD_ONCE_H
+#define LLVM_LIBC_SRC_PTHREAD_PTHREAD_ONCE_H
 
 #include <pthread.h>
 
@@ -17,4 +17,4 @@ int pthread_once(pthread_once_t *flag, __pthread_once_func_t func);
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_THREADS_PTHREAD_ONCE_H
+#endif // LLVM_LIBC_SRC_PTHREAD_PTHREAD_ONCE_H
diff --git a/libc/src/pthread/pthread_self.h b/libc/src/pthread/pthread_self.h
index dd4b920a0b04b..1c4080bb9f632 100644
--- a/libc/src/pthread/pthread_self.h
+++ b/libc/src/pthread/pthread_self.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_THREADS_PTHREAD_SELF_H
-#define LLVM_LIBC_SRC_THREADS_PTHREAD_SELF_H
+#ifndef LLVM_LIBC_SRC_PTHREAD_PTHREAD_SELF_H
+#define LLVM_LIBC_SRC_PTHREAD_PTHREAD_SELF_H
 
 #include <pthread.h>
 
@@ -17,4 +17,4 @@ pthread_t pthread_self();
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_THREADS_PTHREAD_SELF_H
+#endif // LLVM_LIBC_SRC_PTHREAD_PTHREAD_SELF_H
diff --git a/libc/src/sched/sched_getaffinity.h b/libc/src/sched/sched_getaffinity.h
index 9b0c7a29a3822..12317729b02ba 100644
--- a/libc/src/sched/sched_getaffinity.h
+++ b/libc/src/sched/sched_getaffinity.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_UNISTD_SCHED_GETAFFINITY_H
-#define LLVM_LIBC_SRC_UNISTD_SCHED_GETAFFINITY_H
+#ifndef LLVM_LIBC_SRC_SCHED_SCHED_GETAFFINITY_H
+#define LLVM_LIBC_SRC_SCHED_SCHED_GETAFFINITY_H
 
 #include <sched.h>
 
@@ -17,4 +17,4 @@ int sched_getaffinity(pid_t tid, size_t cpuset_size, cpu_set_t *mask);
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_UNISTD_SCHED_GETAFFINITY_H
+#endif // LLVM_LIBC_SRC_SCHED_SCHED_GETAFFINITY_H
diff --git a/libc/src/sched/sched_getcpucount.h b/libc/src/sched/sched_getcpucount.h
index afa3e3c08c442..f55ec147d5825 100644
--- a/libc/src/sched/sched_getcpucount.h
+++ b/libc/src/sched/sched_getcpucount.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_UNISTD_SCHED_GETCPUCOUNT_H
-#define LLVM_LIBC_SRC_UNISTD_SCHED_GETCPUCOUNT_H
+#ifndef LLVM_LIBC_SRC_SCHED_SCHED_GETCPUCOUNT_H
+#define LLVM_LIBC_SRC_SCHED_SCHED_GETCPUCOUNT_H
 
 #include <sched.h>
 #include <stddef.h>
@@ -20,4 +20,4 @@ int __sched_getcpucount(size_t cpuset_size, const cpu_set_t *mask);
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_UNISTD_SCHED_GETCPUCOUNT_H
+#endif // LLVM_LIBC_SRC_SCHED_SCHED_GETCPUCOUNT_H
diff --git a/libc/src/sched/sched_setaffinity.h b/libc/src/sched/sched_setaffinity.h
index ad630b13ac224..9f3f8fe3b1748 100644
--- a/libc/src/sched/sched_setaffinity.h
+++ b/libc/src/sched/sched_setaffinity.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_UNISTD_SCHED_SETAFFINITY_H
-#define LLVM_LIBC_SRC_UNISTD_SCHED_SETAFFINITY_H
+#ifndef LLVM_LIBC_SRC_SCHED_SCHED_SETAFFINITY_H
+#define LLVM_LIBC_SRC_SCHED_SCHED_SETAFFINITY_H
 
 #include <sched.h>
 
@@ -17,4 +17,4 @@ int sched_setaffinity(pid_t pid, size_t cpuset_size, const cpu_set_t *mask);
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_UNISTD_SCHED_SETAFFINITY_H
+#endif // LLVM_LIBC_SRC_SCHED_SCHED_SETAFFINITY_H
diff --git a/libc/src/setjmp/longjmp.h b/libc/src/setjmp/longjmp.h
index 05d8baaa43913..5937504cf7e08 100644
--- a/libc/src/setjmp/longjmp.h
+++ b/libc/src/setjmp/longjmp.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_LONGJMP_LONGJMP_H
-#define LLVM_LIBC_SRC_LONGJMP_LONGJMP_H
+#ifndef LLVM_LIBC_SRC_SETJMP_LONGJMP_H
+#define LLVM_LIBC_SRC_SETJMP_LONGJMP_H
 
 #include <setjmp.h>
 
@@ -17,4 +17,4 @@ void longjmp(__jmp_buf *buf, int val);
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_LONGJMP_LONGJMP_H
+#endif // LLVM_LIBC_SRC_SETJMP_LONGJMP_H
diff --git a/libc/src/setjmp/setjmp_impl.h b/libc/src/setjmp/setjmp_impl.h
index 6b5115e112a56..9dc5396d58b46 100644
--- a/libc/src/setjmp/setjmp_impl.h
+++ b/libc/src/setjmp/setjmp_impl.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SETJMP_SETJMP_H
-#define LLVM_LIBC_SRC_SETJMP_SETJMP_H
+#ifndef LLVM_LIBC_SRC_SETJMP_SETJMP_IMPL_H
+#define LLVM_LIBC_SRC_SETJMP_SETJMP_IMPL_H
 
 // This header has the _impl prefix in its name to avoid conflict with the
 // public header setjmp.h which is also included. here.
@@ -19,4 +19,4 @@ int setjmp(__jmp_buf *buf);
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SETJMP_SETJMP_H
+#endif // LLVM_LIBC_SRC_SETJMP_SETJMP_IMPL_H
diff --git a/libc/src/signal/sigaddset.h b/libc/src/signal/sigaddset.h
index 8d72f7767bbf8..7d4613e32c036 100644
--- a/libc/src/signal/sigaddset.h
+++ b/libc/src/signal/sigaddset.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SIGNAL_SIGEADDSET_H
-#define LLVM_LIBC_SRC_SIGNAL_SIGEADDSET_H
+#ifndef LLVM_LIBC_SRC_SIGNAL_SIGADDSET_H
+#define LLVM_LIBC_SRC_SIGNAL_SIGADDSET_H
 
 #include <signal.h>
 
@@ -17,4 +17,4 @@ int sigaddset(sigset_t *set, int signum);
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SIGNAL_SIGEADDSET_H
+#endif // LLVM_LIBC_SRC_SIGNAL_SIGADDSET_H
diff --git a/libc/src/signal/sigaltstack.h b/libc/src/signal/sigaltstack.h
index f6c8a4bebe3f1..7cc77aad883aa 100644
--- a/libc/src/signal/sigaltstack.h
+++ b/libc/src/signal/sigaltstack.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SIGNAL_SIGALSTACK_H
-#define LLVM_LIBC_SRC_SIGNAL_SIGALSTACK_H
+#ifndef LLVM_LIBC_SRC_SIGNAL_SIGALTSTACK_H
+#define LLVM_LIBC_SRC_SIGNAL_SIGALTSTACK_H
 
 #include <signal.h>
 
@@ -17,4 +17,4 @@ int sigaltstack(const stack_t *__restrict ss, stack_t *__restrict oss);
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SIGNAL_SIGALSTACK_H
+#endif // LLVM_LIBC_SRC_SIGNAL_SIGALTSTACK_H
diff --git a/libc/src/stdlib/_Exit.h b/libc/src/stdlib/_Exit.h
index 5389973ffc5d1..f4ae3266ff301 100644
--- a/libc/src/stdlib/_Exit.h
+++ b/libc/src/stdlib/_Exit.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC__EXIT_H
-#define LLVM_LIBC_SRC__EXIT_H
+#ifndef LLVM_LIBC_SRC_STDLIB__EXIT_H
+#define LLVM_LIBC_SRC_STDLIB__EXIT_H
 
 namespace __llvm_libc {
 
@@ -15,4 +15,4 @@ namespace __llvm_libc {
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC__EXIT_H
+#endif // LLVM_LIBC_SRC_STDLIB__EXIT_H
diff --git a/libc/src/stdlib/abort.h b/libc/src/stdlib/abort.h
index 17f9544816632..d1e4385b6c6e2 100644
--- a/libc/src/stdlib/abort.h
+++ b/libc/src/stdlib/abort.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_ABORT_H
-#define LLVM_LIBC_SRC_ABORT_H
+#ifndef LLVM_LIBC_SRC_STDLIB_ABORT_H
+#define LLVM_LIBC_SRC_STDLIB_ABORT_H
 
 namespace __llvm_libc {
 
@@ -15,4 +15,4 @@ namespace __llvm_libc {
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_ABORT_H
+#endif // LLVM_LIBC_SRC_STDLIB_ABORT_H
diff --git a/libc/src/stdlib/atof.h b/libc/src/stdlib/atof.h
index ea531cc08d438..c897a7e410ae5 100644
--- a/libc/src/stdlib/atof.h
+++ b/libc/src/stdlib/atof.h
@@ -15,4 +15,4 @@ double atof(const char *str);
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_STDLIB_ATOI_H
+#endif // LLVM_LIBC_SRC_STDLIB_ATOF_H
diff --git a/libc/src/stdlib/bsearch.h b/libc/src/stdlib/bsearch.h
index 6cab8f736dea0..aab86dcd71984 100644
--- a/libc/src/stdlib/bsearch.h
+++ b/libc/src/stdlib/bsearch.h
@@ -6,6 +6,9 @@
 //
 //===----------------------------------------------------------------------===//
 
+#ifndef LLVM_LIBC_SRC_STDLIB_BSEARCH_H
+#define LLVM_LIBC_SRC_STDLIB_BSEARCH_H
+
 #include <stdlib.h>
 
 namespace __llvm_libc {
@@ -14,3 +17,5 @@ void *bsearch(const void *key, const void *array, size_t array_size,
               size_t elem_size, int (*compare)(const void *, const void *));
 
 } // namespace __llvm_libc
+
+#endif //LLVM_LIBC_SRC_STDLIB_BSEARCH_H
diff --git a/libc/src/stdlib/div.h b/libc/src/stdlib/div.h
index ec1ded78a0abf..46d59485bf517 100644
--- a/libc/src/stdlib/div.h
+++ b/libc/src/stdlib/div.h
@@ -6,11 +6,11 @@
 //
 //===----------------------------------------------------------------------===//
 
-#include <stdlib.h>
-
 #ifndef LLVM_LIBC_SRC_STDLIB_DIV_H
 #define LLVM_LIBC_SRC_STDLIB_DIV_H
 
+#include <stdlib.h>
+
 namespace __llvm_libc {
 
 div_t div(int x, int y);
diff --git a/libc/src/stdlib/exit.h b/libc/src/stdlib/exit.h
index fb3b20daf6587..cbd9f9720cd39 100644
--- a/libc/src/stdlib/exit.h
+++ b/libc/src/stdlib/exit.h
@@ -6,11 +6,11 @@
 //
 //===----------------------------------------------------------------------===//
 
-#include <stdlib.h>
-
 #ifndef LLVM_LIBC_SRC_STDLIB_EXIT_H
 #define LLVM_LIBC_SRC_STDLIB_EXIT_H
 
+#include <stdlib.h>
+
 namespace __llvm_libc {
 
 [[noreturn]] void exit(int status);
diff --git a/libc/src/stdlib/ldiv.h b/libc/src/stdlib/ldiv.h
index f4e7730a522fe..ab2fe0961b32e 100644
--- a/libc/src/stdlib/ldiv.h
+++ b/libc/src/stdlib/ldiv.h
@@ -6,11 +6,11 @@
 //
 //===----------------------------------------------------------------------===//
 
-#include <stdlib.h>
-
 #ifndef LLVM_LIBC_SRC_STDLIB_LDIV_H
 #define LLVM_LIBC_SRC_STDLIB_LDIV_H
 
+#include <stdlib.h>
+
 namespace __llvm_libc {
 
 ldiv_t ldiv(long x, long y);
diff --git a/libc/src/stdlib/lldiv.h b/libc/src/stdlib/lldiv.h
index 7f0de5c99393a..b361e4e1aaa36 100644
--- a/libc/src/stdlib/lldiv.h
+++ b/libc/src/stdlib/lldiv.h
@@ -5,16 +5,15 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-
-#include <stdlib.h>
-
 #ifndef LLVM_LIBC_SRC_STDLIB_LLDIV_H
 #define LLVM_LIBC_SRC_STDLIB_LLDIV_H
 
+#include <stdlib.h>
+
 namespace __llvm_libc {
 
 lldiv_t lldiv(long long x, long long y);
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_STDLIB_LDIV_H
+#endif // LLVM_LIBC_SRC_STDLIB_LLDIV_H
diff --git a/libc/src/stdlib/rand.h b/libc/src/stdlib/rand.h
index 3f37c5739af87..b421161f6388f 100644
--- a/libc/src/stdlib/rand.h
+++ b/libc/src/stdlib/rand.h
@@ -6,11 +6,11 @@
 //
 //===----------------------------------------------------------------------===//
 
-#include <stdlib.h>
-
 #ifndef LLVM_LIBC_SRC_STDLIB_RAND_H
 #define LLVM_LIBC_SRC_STDLIB_RAND_H
 
+#include <stdlib.h>
+
 namespace __llvm_libc {
 
 int rand(void);
diff --git a/libc/src/stdlib/srand.h b/libc/src/stdlib/srand.h
index 86228b7a6e820..ff2f138ea2222 100644
--- a/libc/src/stdlib/srand.h
+++ b/libc/src/stdlib/srand.h
@@ -6,11 +6,11 @@
 //
 //===----------------------------------------------------------------------===//
 
-#include <stdlib.h>
-
 #ifndef LLVM_LIBC_SRC_STDLIB_SRAND_H
 #define LLVM_LIBC_SRC_STDLIB_SRAND_H
 
+#include <stdlib.h>
+
 namespace __llvm_libc {
 
 void srand(unsigned int seed);
diff --git a/libc/src/string/allocating_string_utils.h b/libc/src/string/allocating_string_utils.h
index 2ca01b9a35bd1..c373868deb427 100644
--- a/libc/src/string/allocating_string_utils.h
+++ b/libc/src/string/allocating_string_utils.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LIBC_SRC_STRING_ALLOCATING_STRING_UTILS_H
-#define LIBC_SRC_STRING_ALLOCATING_STRING_UTILS_H
+#ifndef LLVM_LIBC_SRC_STRING_ALLOCATING_STRING_UTILS_H
+#define LLVM_LIBC_SRC_STRING_ALLOCATING_STRING_UTILS_H
 
 #include "src/__support/CPP/new.h"
 #include "src/__support/CPP/optional.h"
@@ -35,4 +35,4 @@ LIBC_INLINE cpp::optional<char *> strdup(const char *src) {
 } // namespace internal
 } // namespace __llvm_libc
 
-#endif
+#endif // LLVM_LIBC_SRC_STRING_ALLOCATING_STRING_UTILS_H
diff --git a/libc/src/string/memory_utils/utils.h b/libc/src/string/memory_utils/utils.h
index 8f3b9da67669d..66749465ee284 100644
--- a/libc/src/string/memory_utils/utils.h
+++ b/libc/src/string/memory_utils/utils.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_MEMORY_UTILS_UTILS_H
-#define LLVM_LIBC_SRC_MEMORY_UTILS_UTILS_H
+#ifndef LLVM_LIBC_SRC_STRING_MEMORY_UTILS_UTILS_H
+#define LLVM_LIBC_SRC_STRING_MEMORY_UTILS_UTILS_H
 
 #include "src/__support/CPP/bit.h"
 #include "src/__support/CPP/cstddef.h"
@@ -374,4 +374,4 @@ template <size_t SIZE> struct AlignHelper {
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_MEMORY_UTILS_UTILS_H
+#endif // LLVM_LIBC_SRC_STRING_MEMORY_UTILS_UTILS_H
diff --git a/libc/src/string/memory_utils/x86_64/inline_bcmp.h b/libc/src/string/memory_utils/x86_64/inline_bcmp.h
index 00a8cdd2e9e37..96a22f7740a8c 100644
--- a/libc/src/string/memory_utils/x86_64/inline_bcmp.h
+++ b/libc/src/string/memory_utils/x86_64/inline_bcmp.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LIBC_SRC_STRING_MEMORY_UTILS_X86_64_INLINE_BCMP_H
-#define LIBC_SRC_STRING_MEMORY_UTILS_X86_64_INLINE_BCMP_H
+#ifndef LLVM_LIBC_SRC_STRING_MEMORY_UTILS_X86_64_INLINE_BCMP_H
+#define LLVM_LIBC_SRC_STRING_MEMORY_UTILS_X86_64_INLINE_BCMP_H
 
 #include "src/__support/macros/attributes.h" // LIBC_INLINE
 #include "src/string/memory_utils/op_generic.h"
@@ -90,4 +90,4 @@ inline_bcmp_x86_avx512bw_gt16(CPtr p1, CPtr p2, size_t count) {
 
 } // namespace __llvm_libc
 
-#endif // LIBC_SRC_STRING_MEMORY_UTILS_X86_64_INLINE_BCMP_H
+#endif // LLVM_LIBC_SRC_STRING_MEMORY_UTILS_X86_64_INLINE_BCMP_H
diff --git a/libc/src/string/memory_utils/x86_64/inline_memcmp.h b/libc/src/string/memory_utils/x86_64/inline_memcmp.h
index 98ae038648b89..2569b4ddd63dd 100644
--- a/libc/src/string/memory_utils/x86_64/inline_memcmp.h
+++ b/libc/src/string/memory_utils/x86_64/inline_memcmp.h
@@ -5,8 +5,9 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LIBC_SRC_STRING_MEMORY_UTILS_X86_64_INLINE_MEMCMP_H
-#define LIBC_SRC_STRING_MEMORY_UTILS_X86_64_INLINE_MEMCMP_H
+
+#ifndef LLVM_LIBC_SRC_STRING_MEMORY_UTILS_X86_64_INLINE_MEMCMP_H
+#define LLVM_LIBC_SRC_STRING_MEMORY_UTILS_X86_64_INLINE_MEMCMP_H
 
 #include "src/__support/macros/config.h"       // LIBC_INLINE
 #include "src/__support/macros/optimization.h" // LIBC_UNLIKELY
@@ -90,4 +91,4 @@ LIBC_INLINE MemcmpReturnType inline_memcmp_x86(CPtr p1, CPtr p2, size_t count) {
 
 } // namespace __llvm_libc
 
-#endif // LIBC_SRC_STRING_MEMORY_UTILS_X86_64_INLINE_MEMCMP_H
+#endif // LLVM_LIBC_SRC_STRING_MEMORY_UTILS_X86_64_INLINE_MEMCMP_H
diff --git a/libc/src/string/memory_utils/x86_64/inline_memcpy.h b/libc/src/string/memory_utils/x86_64/inline_memcpy.h
index 77d8ed4a82a6d..7d70a552354f4 100644
--- a/libc/src/string/memory_utils/x86_64/inline_memcpy.h
+++ b/libc/src/string/memory_utils/x86_64/inline_memcpy.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LIBC_SRC_STRING_MEMORY_UTILS_X86_64_INLINE_MEMCPY_H
-#define LIBC_SRC_STRING_MEMORY_UTILS_X86_64_INLINE_MEMCPY_H
+#ifndef LLVM_LIBC_SRC_STRING_MEMORY_UTILS_X86_64_INLINE_MEMCPY_H
+#define LLVM_LIBC_SRC_STRING_MEMORY_UTILS_X86_64_INLINE_MEMCPY_H
 
 #include "src/__support/macros/attributes.h"   // LIBC_INLINE_VAR
 #include "src/__support/macros/config.h"       // LIBC_INLINE
@@ -199,4 +199,4 @@ inline_memcpy_x86_maybe_interpose_repmovsb(Ptr __restrict dst,
 
 } // namespace __llvm_libc
 
-#endif // LIBC_SRC_STRING_MEMORY_UTILS_X86_64_INLINE_MEMCPY_H
+#endif // LLVM_LIBC_SRC_STRING_MEMORY_UTILS_X86_64_INLINE_MEMCPY_H
diff --git a/libc/src/string/memory_utils/x86_64/inline_memmove.h b/libc/src/string/memory_utils/x86_64/inline_memmove.h
index dead616f8d693..22a088823f9ce 100644
--- a/libc/src/string/memory_utils/x86_64/inline_memmove.h
+++ b/libc/src/string/memory_utils/x86_64/inline_memmove.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LIBC_SRC_STRING_MEMORY_UTILS_X86_64_INLINE_MEMMOVE_H
-#define LIBC_SRC_STRING_MEMORY_UTILS_X86_64_INLINE_MEMMOVE_H
+#ifndef LLVM_LIBC_SRC_STRING_MEMORY_UTILS_X86_64_INLINE_MEMMOVE_H
+#define LLVM_LIBC_SRC_STRING_MEMORY_UTILS_X86_64_INLINE_MEMMOVE_H
 
 #include "src/__support/macros/config.h" // LIBC_INLINE
 #include "src/string/memory_utils/op_builtin.h"
@@ -63,4 +63,4 @@ LIBC_INLINE void inline_memmove_x86(Ptr dst, CPtr src, size_t count) {
 
 } // namespace __llvm_libc
 
-#endif // LIBC_SRC_STRING_MEMORY_UTILS_X86_64_INLINE_MEMMOVE_H
+#endif // LLVM_LIBC_SRC_STRING_MEMORY_UTILS_X86_64_INLINE_MEMMOVE_H
diff --git a/libc/src/string/memory_utils/x86_64/inline_memset.h b/libc/src/string/memory_utils/x86_64/inline_memset.h
index 8b5d1b5e33279..54ef33a0c3ade 100644
--- a/libc/src/string/memory_utils/x86_64/inline_memset.h
+++ b/libc/src/string/memory_utils/x86_64/inline_memset.h
@@ -5,8 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#ifndef LIBC_SRC_STRING_MEMORY_UTILS_X86_64_INLINE_MEMSET_H
-#define LIBC_SRC_STRING_MEMORY_UTILS_X86_64_INLINE_MEMSET_H
+#ifndef LLVM_LIBC_SRC_STRING_MEMORY_UTILS_X86_64_INLINE_MEMSET_H
+#define LLVM_LIBC_SRC_STRING_MEMORY_UTILS_X86_64_INLINE_MEMSET_H
 
 #include "src/__support/macros/attributes.h" // LIBC_INLINE
 #include "src/string/memory_utils/op_generic.h"
@@ -62,4 +62,4 @@ inline_memset_x86(Ptr dst, uint8_t value, size_t count) {
 }
 } // namespace __llvm_libc
 
-#endif // LIBC_SRC_STRING_MEMORY_UTILS_X86_64_INLINE_MEMSET_H
+#endif // LLVM_LIBC_SRC_STRING_MEMORY_UTILS_X86_64_INLINE_MEMSET_H
diff --git a/libc/src/string/strcasestr.h b/libc/src/string/strcasestr.h
index 8c4bc51d38a28..b69165471bfdc 100644
--- a/libc/src/string/strcasestr.h
+++ b/libc/src/string/strcasestr.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_STRING_STRCASECMP_H
-#define LLVM_LIBC_SRC_STRING_STRCASECMP_H
+#ifndef LLVM_LIBC_SRC_STRING_STRCASESTR_H
+#define LLVM_LIBC_SRC_STRING_STRCASESTR_H
 
 namespace __llvm_libc {
 
@@ -15,4 +15,4 @@ char *strcasestr(const char *needle, const char *haystack);
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_STRING_STRCASECMP_H
+#endif // LLVM_LIBC_SRC_STRING_STRCASESTR_H
diff --git a/libc/src/string/string_utils.h b/libc/src/string/string_utils.h
index 87dc4c6cd2b4c..e874e5f5f0a69 100644
--- a/libc/src/string/string_utils.h
+++ b/libc/src/string/string_utils.h
@@ -11,8 +11,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LIBC_SRC_STRING_STRING_UTILS_H
-#define LIBC_SRC_STRING_STRING_UTILS_H
+#ifndef LLVM_LIBC_SRC_STRING_STRING_UTILS_H
+#define LLVM_LIBC_SRC_STRING_STRING_UTILS_H
 
 #include "src/__support/CPP/bitset.h"
 #include "src/__support/macros/optimization.h" // LIBC_UNLIKELY
@@ -248,4 +248,4 @@ LIBC_INLINE constexpr static char *strrchr_implementation(const char *src,
 } // namespace internal
 } // namespace __llvm_libc
 
-#endif //  LIBC_SRC_STRING_STRING_UTILS_H
+#endif //  LLVM_LIBC_SRC_STRING_STRING_UTILS_H
diff --git a/libc/src/string/strncasecmp.h b/libc/src/string/strncasecmp.h
index 5ef2dcd4cd120..c596a7afa6242 100644
--- a/libc/src/string/strncasecmp.h
+++ b/libc/src/string/strncasecmp.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_STRING_STRCASECMP_H
-#define LLVM_LIBC_SRC_STRING_STRCASECMP_H
+#ifndef LLVM_LIBC_SRC_STRING_STRNCASECMP_H
+#define LLVM_LIBC_SRC_STRING_STRNCASECMP_H
 
 #include <stddef.h>
 
@@ -17,4 +17,4 @@ int strncasecmp(const char *left, const char *right, size_t n);
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_STRING_STRCASECMP_H
+#endif // LLVM_LIBC_SRC_STRING_STRNCASECMP_H
diff --git a/libc/src/sys/resource/getrlimit.h b/libc/src/sys/resource/getrlimit.h
index b0725ac7abfdb..84c056efe4672 100644
--- a/libc/src/sys/resource/getrlimit.h
+++ b/libc/src/sys/resource/getrlimit.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SYS_STAT_GETRLIMIT_H
-#define LLVM_LIBC_SRC_SYS_STAT_GETRLIMIT_H
+#ifndef LLVM_LIBC_SRC_SYS_RESOURCE_GETRLIMIT_H
+#define LLVM_LIBC_SRC_SYS_RESOURCE_GETRLIMIT_H
 
 #include <sys/resource.h>
 
@@ -17,4 +17,4 @@ int getrlimit(int resource, struct rlimit *lim);
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SYS_STAT_GETRLIMIT_H
+#endif // LLVM_LIBC_SRC_SYS_RESOURCE_GETRLIMIT_H
diff --git a/libc/src/sys/resource/setrlimit.h b/libc/src/sys/resource/setrlimit.h
index 00a0d4346ce31..e6dc00e35714b 100644
--- a/libc/src/sys/resource/setrlimit.h
+++ b/libc/src/sys/resource/setrlimit.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SYS_STAT_SETRLIMIT_H
-#define LLVM_LIBC_SRC_SYS_STAT_SETRLIMIT_H
+#ifndef LLVM_LIBC_SRC_SYS_RESOURCE_SETRLIMIT_H
+#define LLVM_LIBC_SRC_SYS_RESOURCE_SETRLIMIT_H
 
 #include <sys/resource.h>
 
@@ -17,4 +17,4 @@ int setrlimit(int resource, const struct rlimit *lim);
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SYS_STAT_SETRLIMIT_H
+#endif // LLVM_LIBC_SRC_SYS_RESOURCE_SETRLIMIT_H
diff --git a/libc/src/sys/sendfile/sendfile.h b/libc/src/sys/sendfile/sendfile.h
index f28840043d6be..ba9bf97e3af0a 100644
--- a/libc/src/sys/sendfile/sendfile.h
+++ b/libc/src/sys/sendfile/sendfile.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SYS_STAT_SENDFILE_H
-#define LLVM_LIBC_SRC_SYS_STAT_SENDFILE_H
+#ifndef LLVM_LIBC_SRC_SYS_SENDFILE_SENDFILE_H
+#define LLVM_LIBC_SRC_SYS_SENDFILE_SENDFILE_H
 
 #include <sys/sendfile.h>
 
@@ -17,4 +17,4 @@ ssize_t sendfile(int, int, off_t *, size_t);
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SYS_STAT_SENDFILE_H
+#endif // LLVM_LIBC_SRC_SYS_SENDFILE_SENDFILE_H
diff --git a/libc/src/sys/socket/socket.h b/libc/src/sys/socket/socket.h
index 6a5a4c9e623f4..b18aa7f388d83 100644
--- a/libc/src/sys/socket/socket.h
+++ b/libc/src/sys/socket/socket.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SYS_SOCKET_SENDFILE_H
-#define LLVM_LIBC_SRC_SYS_SOCKET_SENDFILE_H
+#ifndef LLVM_LIBC_SRC_SYS_SOCKET_SOCKET_H
+#define LLVM_LIBC_SRC_SYS_SOCKET_SOCKET_H
 
 namespace __llvm_libc {
 
@@ -15,4 +15,4 @@ int socket(int domain, int type, int protocol);
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SYS_SOCKET_SENDFILE_H
+#endif // LLVM_LIBC_SRC_SYS_SOCKET_SOCKET_H
diff --git a/libc/src/sys/stat/linux/kernel_statx.h b/libc/src/sys/stat/linux/kernel_statx.h
index 9417194c58020..48b23065d800f 100644
--- a/libc/src/sys/stat/linux/kernel_statx.h
+++ b/libc/src/sys/stat/linux/kernel_statx.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_SYS_STAT_LINUX_STATX_H
-#define LLVM_LIBC_SRC_SYS_STAT_LINUX_STATX_H
+#ifndef LLVM_LIBC_SRC_SYS_STAT_LINUX_KERNEL_STATX_H
+#define LLVM_LIBC_SRC_SYS_STAT_LINUX_KERNEL_STATX_H
 
 #include "src/__support/OSUtil/syscall.h" // For internal syscall function.
 #include "src/__support/common.h"
@@ -100,4 +100,4 @@ LIBC_INLINE int statx(int dirfd, const char *__restrict path, int flags,
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_SYS_STAT_LINUX_STATX_H
+#endif // LLVM_LIBC_SRC_SYS_STAT_LINUX_KERNEL_STATX_H
diff --git a/libc/src/termios/cfgetispeed.h b/libc/src/termios/cfgetispeed.h
index 8ed6dac6cd51d..9cd3a4bac88f8 100644
--- a/libc/src/termios/cfgetispeed.h
+++ b/libc/src/termios/cfgetispeed.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_UNISTD_CFGETISPEED_H
-#define LLVM_LIBC_SRC_UNISTD_CFGETISPEED_H
+#ifndef LLVM_LIBC_SRC_TERMIOS_CFGETISPEED_H
+#define LLVM_LIBC_SRC_TERMIOS_CFGETISPEED_H
 
 #include <termios.h>
 
@@ -17,4 +17,4 @@ speed_t cfgetispeed(const struct termios *t);
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_UNISTD_CFGETISPEED_H
+#endif // LLVM_LIBC_SRC_TERMIOS_CFGETISPEED_H
diff --git a/libc/src/termios/cfgetospeed.h b/libc/src/termios/cfgetospeed.h
index aafebd984c728..14ff9d018bcb4 100644
--- a/libc/src/termios/cfgetospeed.h
+++ b/libc/src/termios/cfgetospeed.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_UNISTD_CFGETOSPEED_H
-#define LLVM_LIBC_SRC_UNISTD_CFGETOSPEED_H
+#ifndef LLVM_LIBC_SRC_TERMIOS_CFGETOSPEED_H
+#define LLVM_LIBC_SRC_TERMIOS_CFGETOSPEED_H
 
 #include <termios.h>
 
@@ -17,4 +17,4 @@ speed_t cfgetospeed(const struct termios *t);
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_UNISTD_CFGETOSPEED_H
+#endif // LLVM_LIBC_SRC_TERMIOS_CFGETOSPEED_H
diff --git a/libc/src/termios/cfsetispeed.h b/libc/src/termios/cfsetispeed.h
index 7204887b16248..8d1648f10cd32 100644
--- a/libc/src/termios/cfsetispeed.h
+++ b/libc/src/termios/cfsetispeed.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_UNISTD_CFSETISPEED_H
-#define LLVM_LIBC_SRC_UNISTD_CFSETISPEED_H
+#ifndef LLVM_LIBC_SRC_TERMIOS_CFSETISPEED_H
+#define LLVM_LIBC_SRC_TERMIOS_CFSETISPEED_H
 
 #include <termios.h>
 
@@ -17,4 +17,4 @@ int cfsetispeed(struct termios *t, speed_t speed);
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_UNISTD_CFSETISPEED_H
+#endif // LLVM_LIBC_SRC_TERMIOS_CFSETISPEED_H
diff --git a/libc/src/termios/cfsetospeed.h b/libc/src/termios/cfsetospeed.h
index e831bab2b949d..e7bb21b38a880 100644
--- a/libc/src/termios/cfsetospeed.h
+++ b/libc/src/termios/cfsetospeed.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_UNISTD_CFSETOSPEED_H
-#define LLVM_LIBC_SRC_UNISTD_CFSETOSPEED_H
+#ifndef LLVM_LIBC_SRC_TERMIOS_CFSETOSPEED_H
+#define LLVM_LIBC_SRC_TERMIOS_CFSETOSPEED_H
 
 #include <termios.h>
 
@@ -17,4 +17,4 @@ int cfsetospeed(struct termios *t, speed_t speed);
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_UNISTD_CFSETOSPEED_H
+#endif // LLVM_LIBC_SRC_TERMIOS_CFSETOSPEED_H
diff --git a/libc/src/termios/tcdrain.h b/libc/src/termios/tcdrain.h
index 908d821378b90..1bde86d890b0f 100644
--- a/libc/src/termios/tcdrain.h
+++ b/libc/src/termios/tcdrain.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_UNISTD_TCDRAIN_H
-#define LLVM_LIBC_SRC_UNISTD_TCDRAIN_H
+#ifndef LLVM_LIBC_SRC_TERMIOS_TCDRAIN_H
+#define LLVM_LIBC_SRC_TERMIOS_TCDRAIN_H
 
 #include <termios.h>
 
@@ -17,4 +17,4 @@ int tcdrain(int fd);
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_UNISTD_TCDRAIN_H
+#endif // LLVM_LIBC_SRC_TERMIOS_TCDRAIN_H
diff --git a/libc/src/termios/tcflow.h b/libc/src/termios/tcflow.h
index 4d45cbfd86eba..4040c2724d56c 100644
--- a/libc/src/termios/tcflow.h
+++ b/libc/src/termios/tcflow.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_UNISTD_TCFLOW_H
-#define LLVM_LIBC_SRC_UNISTD_TCFLOW_H
+#ifndef LLVM_LIBC_SRC_TERMIOS_TCFLOW_H
+#define LLVM_LIBC_SRC_TERMIOS_TCFLOW_H
 
 #include <termios.h>
 
@@ -17,4 +17,4 @@ int tcflow(int fd, int action);
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_UNISTD_TCFLOW_H
+#endif // LLVM_LIBC_SRC_TERMIOS_TCFLOW_H
diff --git a/libc/src/termios/tcflush.h b/libc/src/termios/tcflush.h
index 9dbcca371b466..61fec9baae1a8 100644
--- a/libc/src/termios/tcflush.h
+++ b/libc/src/termios/tcflush.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_UNISTD_TCFLUSH_H
-#define LLVM_LIBC_SRC_UNISTD_TCFLUSH_H
+#ifndef LLVM_LIBC_SRC_TERMIOS_TCFLUSH_H
+#define LLVM_LIBC_SRC_TERMIOS_TCFLUSH_H
 
 #include <termios.h>
 
@@ -17,4 +17,4 @@ int tcflush(int fd, int queue_selector);
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_UNISTD_TCFLUSH_H
+#endif // LLVM_LIBC_SRC_TERMIOS_TCFLUSH_H
diff --git a/libc/src/termios/tcsendbreak.h b/libc/src/termios/tcsendbreak.h
index 7ad169517c222..52d72435ab129 100644
--- a/libc/src/termios/tcsendbreak.h
+++ b/libc/src/termios/tcsendbreak.h
@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIBC_SRC_UNISTD_TCSENDBREAK_H
-#define LLVM_LIBC_SRC_UNISTD_TCSENDBREAK_H
+#ifndef LLVM_LIBC_SRC_TERMIOS_TCSENDBREAK_H
+#define LLVM_LIBC_SRC_TERMIOS_TCSENDBREAK_H
 
 #include <termios.h>
 
@@ -17,4 +17,4 @@ int tcsendbreak(int fd, int duration);
 
 } // namespace __llvm_libc
 
-#endif // LLVM_LIBC_SRC_UNISTD_TCSENDBREAK_H
+#endif // LLVM_LIBC_SRC_TERMIOS_TCSENDBREAK_H