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| author | Michael Munday <mike.munday@ibm.com> | 2019-03-28 12:51:30 -0400 |
|---|---|---|
| committer | Michael Munday <mike.munday@ibm.com> | 2019-04-15 13:17:28 +0000 |
| commit | aafe257390cc9048e8b5df898fabd79a9e0d4c39 (patch) | |
| tree | 2c0636b4b1ab59eb4b00a1f185515ce22ee2ff5a /src/cmd/internal/obj/objfile.go | |
| parent | 0bd101cecc5458a8463b8d672bf1745c3cbb7c02 (diff) | |
| download | go-aafe257390cc9048e8b5df898fabd79a9e0d4c39.tar.xz | |
cmd/link, runtime: mark goexit as the top of the call stack
This CL adds a new attribute, TOPFRAME, which can be used to mark
functions that should be treated as being at the top of the call
stack. The function `runtime.goexit` has been marked this way on
architectures that use a link register.
This will stop programs that use DWARF to unwind the call stack
from unwinding past `runtime.goexit` on architectures that use a
link register. For example, it eliminates "corrupt stack?"
warnings when generating a backtrace that hits `runtime.goexit`
in GDB on s390x.
Similar code should be added for non-link-register architectures
(i.e. amd64, 386). They mark the top of the call stack slightly
differently to link register architectures so I haven't added
that code (they need to mark "rip" as undefined).
Fixes #24385.
Change-Id: I15b4c69ac75b491daa0acf0d981cb80eb06488de
Reviewed-on: https://go-review.googlesource.com/c/go/+/169726
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Diffstat (limited to 'src/cmd/internal/obj/objfile.go')
| -rw-r--r-- | src/cmd/internal/obj/objfile.go | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/src/cmd/internal/obj/objfile.go b/src/cmd/internal/obj/objfile.go index a94717a404..0aa0d2ac44 100644 --- a/src/cmd/internal/obj/objfile.go +++ b/src/cmd/internal/obj/objfile.go @@ -230,6 +230,9 @@ func (w *objWriter) writeSymDebug(s *LSym) { if s.NoSplit() { fmt.Fprintf(ctxt.Bso, "nosplit ") } + if s.TopFrame() { + fmt.Fprintf(ctxt.Bso, "topframe ") + } fmt.Fprintf(ctxt.Bso, "size=%d", s.Size) if s.Type == objabi.STEXT { fmt.Fprintf(ctxt.Bso, " args=%#x locals=%#x", uint64(s.Func.Args), uint64(s.Func.Locals)) @@ -342,6 +345,9 @@ func (w *objWriter) writeSym(s *LSym) { if ctxt.Flag_shared { flags |= 1 << 3 } + if s.TopFrame() { + flags |= 1 << 4 + } w.writeInt(flags) w.writeInt(int64(len(s.Func.Autom))) for _, a := range s.Func.Autom { |