diff --git a/scram-tools.file/tools/llvm/llvm-cxxcompiler.xml b/scram-tools.file/tools/llvm/llvm-cxxcompiler.xml
index 9130dae09af..234a965f146 100644
--- a/scram-tools.file/tools/llvm/llvm-cxxcompiler.xml
+++ b/scram-tools.file/tools/llvm/llvm-cxxcompiler.xml
@@ -17,6 +17,8 @@
     <flags REM_CXXFLAGS="-fno-crossjumping"/>
     <flags REM_CXXFLAGS="-fno-aggressive-loop-optimizations"/>
     <flags REM_CXXFLAGS="-funroll-all-loops"/>
+    <flags REM_LTO_FLAGS="-fipa-icf"/>
+    <flags REM_LTO_FLAGS="-flto-odr-type-merging"/>
     <flags CXXFLAGS="-Wno-c99-extensions"/>
     <flags CXXFLAGS="-Wno-c++11-narrowing"/>
     <flags CXXFLAGS="-D__STRICT_ANSI__"/>