From: Andrew Gerrand Date: Fri, 1 Nov 2013 00:24:11 +0000 (+1100) Subject: [release-branch.go1.2] debug/dwarf: add DWARF 4 form constants X-Git-Tag: go1.2rc3~14 X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=744d53cdeb9a6727622d5efeb92c18a7976cc119;p=gostls13.git [release-branch.go1.2] debug/dwarf: add DWARF 4 form constants ««« CL 18460043 / 08e6655618f5 debug/dwarf: add DWARF 4 form constants Some versions of clang generate DWARF 4-format attributes even when using -gdwarf-2. We don't care much about the values, but we do need to be able to parse past them. This fixes a bug in Go 1.2 rc2 reported via private mail using a near-tip version of clang. R=golang-dev, iant, dvyukov CC=golang-dev https://golang.org/cl/18460043 »»» R=golang-dev CC=golang-dev https://golang.org/cl/20470045 --- diff --git a/src/pkg/debug/dwarf/const.go b/src/pkg/debug/dwarf/const.go index ad696dc326..9d32a0af2a 100644 --- a/src/pkg/debug/dwarf/const.go +++ b/src/pkg/debug/dwarf/const.go @@ -207,7 +207,10 @@ const ( formRef8 format = 0x14 formRefUdata format = 0x15 formIndirect format = 0x16 + formSecOffset format = 0x17 + formExprloc format = 0x18 formFlagPresent format = 0x19 + formRefSig8 format = 0x20 ) // A Tag is the classification (the type) of an Entry. diff --git a/src/pkg/debug/dwarf/entry.go b/src/pkg/debug/dwarf/entry.go index 6e6fa0f590..c0c2889923 100644 --- a/src/pkg/debug/dwarf/entry.go +++ b/src/pkg/debug/dwarf/entry.go @@ -188,6 +188,7 @@ func (b *buf) entry(atab abbrevTable, ubase Offset) *Entry { // flag case formFlag: val = b.uint8() == 1 + // New in DWARF 4. case formFlagPresent: // The attribute is implicitly indicated as present, and no value is // encoded in the debugging information entry itself. @@ -236,6 +237,30 @@ func (b *buf) entry(atab abbrevTable, ubase Offset) *Entry { b.err = b1.err return nil } + + // lineptr, loclistptr, macptr, rangelistptr + // New in DWARF 4, but clang can generate them with -gdwarf-2. + // Section reference, replacing use of formData4 and formData8. + case formSecOffset: + is64, known := b.format.dwarf64() + if !known { + b.error("unknown size for DW_FORM_sec_offset") + } else if is64 { + val = int64(b.uint64()) + } else { + val = int64(b.uint32()) + } + + // exprloc + // New in DWARF 4. + case formExprloc: + val = b.bytes(int(b.uint())) + + // reference + // New in DWARF 4. + case formRefSig8: + // 64-bit type signature. + val = b.uint64() } e.Field[i].Val = val }