proc: correctly set G struct offset for 1.11

The offset of G changed in go1.11 from 0x8a0 to 0x30. See:
golang/go#23617

pkg/goversion/go_version.go

@@ -153,11 +153,26 @@ func Installed() (GoVersion, bool) {
 }
 
 // RuntimeAfterOrEqual checks that the runtime version is major.minor or a
-// later version or a development version.
+// later version, or a development version.
 func RuntimeAfterOrEqual(major, minor int) bool {
 	ver, _ := Parse(runtime.Version())
 	if ver.IsDevel() {
 		return true
 	}
 	return ver.AfterOrEqual(GoVersion{major, minor, -1, 0, 0, ""})
 }
+
+const producerVersionPrefix = "Go cmd/compile "
+
+// ProducerAfterOrEqual checks that the DW_AT_producer version is
+// major.minor or a later version, or a development version.
+func ProducerAfterOrEqual(producer string, major, minor int) bool {
+	if strings.HasPrefix(producer, producerVersionPrefix) {
+		producer = producer[len(producerVersionPrefix):]
+	}
+	ver, _ := Parse(producer)
+	if ver.IsDevel() {
+		return true
+	}
+	return ver.AfterOrEqual(GoVersion{major, minor, -1, 0, 0, ""})
+}

pkg/proc/bininfo.go

@@ -21,6 +21,7 @@ import (
 	"github.com/derekparker/delve/pkg/dwarf/line"
 	"github.com/derekparker/delve/pkg/dwarf/op"
 	"github.com/derekparker/delve/pkg/dwarf/reader"
+	"github.com/derekparker/delve/pkg/goversion"
 )
 
 type BinaryInfo struct {
@@ -75,7 +76,8 @@ type compileUnit struct {
 	Name          string              // univocal name for non-go compile units
 	lineInfo      *line.DebugLineInfo // debug_line segment associated with this compile unit
 	LowPC, HighPC uint64
-	optimized     bool // this compile unit is optimized
+	optimized     bool   // this compile unit is optimized
+	producer      string // producer attribute
 }
 
 // Function describes a function in the target program.
@@ -351,7 +353,7 @@ func (bi *BinaryInfo) LoadFromData(dwdata *dwarf.Data, debugFrameBytes, debugLin
 
 	bi.loclistInit(debugLocBytes)
 
-	bi.loadDebugInfoMaps(debugLineBytes, nil)
+	bi.loadDebugInfoMaps(debugLineBytes, nil, nil)
 }
 
 func (bi *BinaryInfo) loclistInit(data []byte) {
@@ -426,6 +428,15 @@ func (bi *BinaryInfo) findCompileUnit(pc uint64) *compileUnit {
 	return nil
 }
 
+func (bi *BinaryInfo) Producer() string {
+	for _, cu := range bi.compileUnits {
+		if cu.isgo && cu.producer != "" {
+			return cu.producer
+		}
+	}
+	return ""
+}
+
 // ELF ///////////////////////////////////////////////////////////////
 
 func (bi *BinaryInfo) LoadBinaryInfoElf(path string, wg *sync.WaitGroup) error {
@@ -456,7 +467,7 @@ func (bi *BinaryInfo) LoadBinaryInfoElf(path string, wg *sync.WaitGroup) error {
 
 	wg.Add(3)
 	go bi.parseDebugFrameElf(elfFile, wg)
-	go bi.loadDebugInfoMaps(debugLineBytes, wg)
+	go bi.loadDebugInfoMaps(debugLineBytes, wg, nil)
 	go bi.setGStructOffsetElf(elfFile, wg)
 	return nil
 }
@@ -568,7 +579,7 @@ func (bi *BinaryInfo) LoadBinaryInfoPE(path string, wg *sync.WaitGroup) error {
 
 	wg.Add(2)
 	go bi.parseDebugFramePE(peFile, wg)
-	go bi.loadDebugInfoMaps(debugLineBytes, wg)
+	go bi.loadDebugInfoMaps(debugLineBytes, wg, nil)
 
 	// Use ArbitraryUserPointer (0x28) as pointer to pointer
 	// to G struct per:
@@ -736,11 +747,22 @@ func (bi *BinaryInfo) LoadBinaryInfoMacho(path string, wg *sync.WaitGroup) error
 
 	wg.Add(2)
 	go bi.parseDebugFrameMacho(exe, wg)
-	go bi.loadDebugInfoMaps(debugLineBytes, wg)
-	bi.gStructOffset = 0x8a0
+	go bi.loadDebugInfoMaps(debugLineBytes, wg, bi.setGStructOffsetMacho)
 	return nil
 }
 
+func (bi *BinaryInfo) setGStructOffsetMacho() {
+	// In go1.11 it's 0x30, before 0x8a0, see:
+	// https://github.com/golang/go/issues/23617
+	// and go commit b3a854c733257c5249c3435ffcee194f8439676a
+	producer := bi.Producer()
+	if producer != "" && goversion.ProducerAfterOrEqual(producer, 1, 11) {
+		bi.gStructOffset = 0x30
+		return
+	}
+	bi.gStructOffset = 0x8a0
+}
+
 func (bi *BinaryInfo) parseDebugFrameMacho(exe *macho.File, wg *sync.WaitGroup) {
 	defer wg.Done()
 

pkg/proc/types.go

@@ -177,7 +177,7 @@ func (v packageVarsByAddr) Len() int               { return len(v) }
 func (v packageVarsByAddr) Less(i int, j int) bool { return v[i].addr < v[j].addr }
 func (v packageVarsByAddr) Swap(i int, j int)      { v[i], v[j] = v[j], v[i] }
 
-func (bi *BinaryInfo) loadDebugInfoMaps(debugLineBytes []byte, wg *sync.WaitGroup) {
+func (bi *BinaryInfo) loadDebugInfoMaps(debugLineBytes []byte, wg *sync.WaitGroup, cont func()) {
 	if wg != nil {
 		defer wg.Done()
 	}
@@ -212,9 +212,15 @@ func (bi *BinaryInfo) loadDebugInfoMaps(debugLineBytes []byte, wg *sync.WaitGrou
 			if lineInfoOffset >= 0 && lineInfoOffset < int64(len(debugLineBytes)) {
 				cu.lineInfo = line.Parse(compdir, bytes.NewBuffer(debugLineBytes[lineInfoOffset:]))
 			}
-			if producer, _ := entry.Val(dwarf.AttrProducer).(string); cu.isgo && producer != "" {
-				semicolon := strings.Index(producer, ";")
-				cu.optimized = semicolon < 0 || !strings.Contains(producer[semicolon:], "-N") || !strings.Contains(producer[semicolon:], "-l")
+			cu.producer, _ = entry.Val(dwarf.AttrProducer).(string)
+			if cu.isgo {
+				semicolon := strings.Index(cu.producer, ";")
+				if semicolon < 0 {
+					cu.optimized = true
+				} else {
+					cu.optimized = !strings.Contains(cu.producer[semicolon:], "-N") || !strings.Contains(cu.producer[semicolon:], "-l")
+					cu.producer = cu.producer[:semicolon]
+				}
 			}
 			bi.compileUnits = append(bi.compileUnits, cu)
 
@@ -302,6 +308,10 @@ func (bi *BinaryInfo) loadDebugInfoMaps(debugLineBytes []byte, wg *sync.WaitGrou
 	}
 	sort.Strings(bi.Sources)
 	bi.Sources = uniq(bi.Sources)
+
+	if cont != nil {
+		cont()
+	}
 }
 
 func uniq(s []string) []string {