diff --git a/src/cmd/link/internal/ld/dwarf.go b/src/cmd/link/internal/ld/dwarf.go index 959fc8290c..2164fa80a0 100644 --- a/src/cmd/link/internal/ld/dwarf.go +++ b/src/cmd/link/internal/ld/dwarf.go @@ -340,19 +340,19 @@ func lookupOrDiag(ctxt *Link, n string) *sym.Symbol { return s } -func dotypedef(ctxt *Link, parent *dwarf.DWDie, name string, def *dwarf.DWDie) { +func dotypedef(ctxt *Link, parent *dwarf.DWDie, name string, def *dwarf.DWDie) *dwarf.DWDie { // Only emit typedefs for real names. if strings.HasPrefix(name, "map[") { - return + return nil } if strings.HasPrefix(name, "struct {") { - return + return nil } if strings.HasPrefix(name, "chan ") { - return + return nil } if name[0] == '[' || name[0] == '*' { - return + return nil } if def == nil { Errorf(nil, "dwarf: bad def in dotypedef") @@ -370,6 +370,8 @@ func dotypedef(ctxt *Link, parent *dwarf.DWDie, name string, def *dwarf.DWDie) { die := newdie(ctxt, parent, dwarf.DW_ABRV_TYPEDECL, name, 0) newrefattr(die, dwarf.DW_AT_type, s) + + return die } // Define gotype, for composite ones recurse into constituents. @@ -399,7 +401,7 @@ func newtype(ctxt *Link, gotype *sym.Symbol) *dwarf.DWDie { kind := decodetypeKind(ctxt.Arch, gotype) bytesize := decodetypeSize(ctxt.Arch, gotype) - var die *dwarf.DWDie + var die, typedefdie *dwarf.DWDie switch kind { case objabi.KindBool: die = newdie(ctxt, &dwtypes, dwarf.DW_ABRV_BASETYPE, name, 0) @@ -439,7 +441,7 @@ func newtype(ctxt *Link, gotype *sym.Symbol) *dwarf.DWDie { case objabi.KindArray: die = newdie(ctxt, &dwtypes, dwarf.DW_ABRV_ARRAYTYPE, name, 0) - dotypedef(ctxt, &dwtypes, name, die) + typedefdie = dotypedef(ctxt, &dwtypes, name, die) newattr(die, dwarf.DW_AT_byte_size, dwarf.DW_CLS_CONSTANT, bytesize, 0) s := decodetypeArrayElem(ctxt.Arch, gotype) newrefattr(die, dwarf.DW_AT_type, defgotype(ctxt, s)) @@ -461,7 +463,7 @@ func newtype(ctxt *Link, gotype *sym.Symbol) *dwarf.DWDie { case objabi.KindFunc: die = newdie(ctxt, &dwtypes, dwarf.DW_ABRV_FUNCTYPE, name, 0) newattr(die, dwarf.DW_AT_byte_size, dwarf.DW_CLS_CONSTANT, bytesize, 0) - dotypedef(ctxt, &dwtypes, name, die) + typedefdie = dotypedef(ctxt, &dwtypes, name, die) nfields := decodetypeFuncInCount(ctxt.Arch, gotype) for i := 0; i < nfields; i++ { s := decodetypeFuncInType(ctxt.Arch, gotype, i) @@ -481,7 +483,7 @@ func newtype(ctxt *Link, gotype *sym.Symbol) *dwarf.DWDie { case objabi.KindInterface: die = newdie(ctxt, &dwtypes, dwarf.DW_ABRV_IFACETYPE, name, 0) - dotypedef(ctxt, &dwtypes, name, die) + typedefdie = dotypedef(ctxt, &dwtypes, name, die) nfields := int(decodetypeIfaceMethodCount(ctxt.Arch, gotype)) var s *sym.Symbol if nfields == 0 { @@ -503,13 +505,13 @@ func newtype(ctxt *Link, gotype *sym.Symbol) *dwarf.DWDie { case objabi.KindPtr: die = newdie(ctxt, &dwtypes, dwarf.DW_ABRV_PTRTYPE, name, 0) - dotypedef(ctxt, &dwtypes, name, die) + typedefdie = dotypedef(ctxt, &dwtypes, name, die) s := decodetypePtrElem(ctxt.Arch, gotype) newrefattr(die, dwarf.DW_AT_type, defgotype(ctxt, s)) case objabi.KindSlice: die = newdie(ctxt, &dwtypes, dwarf.DW_ABRV_SLICETYPE, name, 0) - dotypedef(ctxt, &dwtypes, name, die) + typedefdie = dotypedef(ctxt, &dwtypes, name, die) newattr(die, dwarf.DW_AT_byte_size, dwarf.DW_CLS_CONSTANT, bytesize, 0) s := decodetypeArrayElem(ctxt.Arch, gotype) elem := defgotype(ctxt, s) @@ -521,7 +523,7 @@ func newtype(ctxt *Link, gotype *sym.Symbol) *dwarf.DWDie { case objabi.KindStruct: die = newdie(ctxt, &dwtypes, dwarf.DW_ABRV_STRUCTTYPE, name, 0) - dotypedef(ctxt, &dwtypes, name, die) + typedefdie = dotypedef(ctxt, &dwtypes, name, die) newattr(die, dwarf.DW_AT_byte_size, dwarf.DW_CLS_CONSTANT, bytesize, 0) nfields := decodetypeStructFieldCount(ctxt.Arch, gotype) for i := 0; i < nfields; i++ { @@ -557,6 +559,9 @@ func newtype(ctxt *Link, gotype *sym.Symbol) *dwarf.DWDie { prototypedies[gotype.Name] = die } + if typedefdie != nil { + return typedefdie + } return die } diff --git a/src/cmd/link/internal/ld/dwarf_test.go b/src/cmd/link/internal/ld/dwarf_test.go index 157bebbb41..5d2aadf589 100644 --- a/src/cmd/link/internal/ld/dwarf_test.go +++ b/src/cmd/link/internal/ld/dwarf_test.go @@ -948,3 +948,117 @@ func main() { t.Errorf("DWARF type offset was %#x+%#x, but test program said %#x", rtAttr.(uint64), types.Addr, addr) } } + +func TestIssue27614(t *testing.T) { + // Type references in debug_info should always use the DW_TAG_typedef_type + // for the type, when that's generated. + + testenv.MustHaveGoBuild(t) + + if runtime.GOOS == "plan9" { + t.Skip("skipping on plan9; no DWARF symbol table in executables") + } + + dir, err := ioutil.TempDir("", "go-build") + if err != nil { + t.Fatal(err) + } + defer os.RemoveAll(dir) + + const prog = `package main + +import "fmt" + +type astruct struct { + X int +} + +type bstruct struct { + X float32 +} + +var globalptr *astruct +var globalvar astruct +var bvar0, bvar1, bvar2 bstruct + +func main() { + fmt.Println(globalptr, globalvar, bvar0, bvar1, bvar2) +} +` + + f := gobuild(t, dir, prog, NoOpt) + + defer f.Close() + + data, err := f.DWARF() + if err != nil { + t.Fatal(err) + } + + rdr := data.Reader() + + var astructTypeDIE, bstructTypeDIE, ptrastructTypeDIE *dwarf.Entry + var globalptrDIE, globalvarDIE *dwarf.Entry + var bvarDIE [3]*dwarf.Entry + + for { + e, err := rdr.Next() + if err != nil { + t.Fatal(err) + } + if e == nil { + break + } + + name, _ := e.Val(dwarf.AttrName).(string) + + switch e.Tag { + case dwarf.TagTypedef: + switch name { + case "main.astruct": + astructTypeDIE = e + case "main.bstruct": + bstructTypeDIE = e + } + case dwarf.TagPointerType: + if name == "*main.astruct" { + ptrastructTypeDIE = e + } + case dwarf.TagVariable: + switch name { + case "main.globalptr": + globalptrDIE = e + case "main.globalvar": + globalvarDIE = e + default: + const bvarprefix = "main.bvar" + if strings.HasPrefix(name, bvarprefix) { + i, _ := strconv.Atoi(name[len(bvarprefix):]) + bvarDIE[i] = e + } + } + } + } + + typedieof := func(e *dwarf.Entry) dwarf.Offset { + return e.Val(dwarf.AttrType).(dwarf.Offset) + } + + if off := typedieof(ptrastructTypeDIE); off != astructTypeDIE.Offset { + t.Errorf("type attribute of *main.astruct references %#x, not main.astruct DIE at %#x\n", off, astructTypeDIE.Offset) + } + + if off := typedieof(globalptrDIE); off != ptrastructTypeDIE.Offset { + t.Errorf("type attribute of main.globalptr references %#x, not *main.astruct DIE at %#x\n", off, ptrastructTypeDIE.Offset) + } + + if off := typedieof(globalvarDIE); off != astructTypeDIE.Offset { + t.Errorf("type attribute of main.globalvar1 references %#x, not main.astruct DIE at %#x\n", off, astructTypeDIE.Offset) + } + + for i := range bvarDIE { + if off := typedieof(bvarDIE[i]); off != bstructTypeDIE.Offset { + t.Errorf("type attribute of main.bvar%d references %#x, not main.bstruct DIE at %#x\n", i, off, bstructTypeDIE.Offset) + } + } +}