[Bug go/68562] morestack misaligns stack on x86_64

["trippels at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68562

--- Comment #5 from Markus Trippelsdorf <trippels at gcc dot gnu.org> ---
(In reply to Ian Lance Taylor from comment #4)
> Created attachment 37650 [details]
> Possible patch
> 
> Do you have a way to test whether this patch fixes the problem?

Unfortunately no, because go doesn't compile:

echo timestamp > s-zdefaultcc 
/var/tmp/gcc_build_dir/./gcc/gccgo -B/var/tmp/gcc_build_dir/./gcc/
-B/usr/local/x86_64-pc-linux-gnu/bin/ -B/usr/local/x86_64-pc-linux-gnu/lib/
-isystem /usr/local/x86_64-pc-linux-gnu/include -isystem
/usr/local/x86_64-pc-linux-gnu/sys-include   -g -O2  -static-libstdc++
-static-libgcc  -L ../x86_64-pc-linux-gnu/libgo -L
../x86_64-pc-linux-gnu/libgo/.libs -o go
../../gcc/gotools/../libgo/go/cmd/go/alldocs.go
../../gcc/gotools/../libgo/go/cmd/go/build.go
../../gcc/gotools/../libgo/go/cmd/go/clean.go
../../gcc/gotools/../libgo/go/cmd/go/context.go
../../gcc/gotools/../libgo/go/cmd/go/discovery.go
../../gcc/gotools/../libgo/go/cmd/go/doc.go
../../gcc/gotools/../libgo/go/cmd/go/env.go
../../gcc/gotools/../libgo/go/cmd/go/fix.go
../../gcc/gotools/../libgo/go/cmd/go/fmt.go
../../gcc/gotools/../libgo/go/cmd/go/generate.go
../../gcc/gotools/../libgo/go/cmd/go/get.go
../../gcc/gotools/../libgo/go/cmd/go/go11.go
../../gcc/gotools/../libgo/go/cmd/go/help.go
../../gcc/gotools/../libgo/go/cmd/go/http.go
../../gcc/gotools/../libgo/go/cmd/go/list.go
../../gcc/gotools/../libgo/go/cmd/go/main.go
../../gcc/gotools/../libgo/go/cmd/go/note.go
../../gcc/gotools/../libgo/go/cmd/go/pkg.go
../../gcc/gotools/../libgo/go/cmd/go/run.go
../../gcc/gotools/../libgo/go/cmd/go/signal.go
../../gcc/gotools/../libgo/go/cmd/go/signal_unix.go
../../gcc/gotools/../libgo/go/cmd/go/test.go
../../gcc/gotools/../libgo/go/cmd/go/testflag.go
../../gcc/gotools/../libgo/go/cmd/go/tool.go
../../gcc/gotools/../libgo/go/cmd/go/vcs.go
../../gcc/gotools/../libgo/go/cmd/go/version.go
../../gcc/gotools/../libgo/go/cmd/go/vet.go
../x86_64-pc-linux-gnu/libgo/zstdpkglist.go zdefaultcc.go  
/var/tmp/gcc_build_dir/./gcc/gccgo -B/var/tmp/gcc_build_dir/./gcc/
-B/usr/local/x86_64-pc-linux-gnu/bin/ -B/usr/local/x86_64-pc-linux-gnu/lib/
-isystem /usr/local/x86_64-pc-linux-gnu/include -isystem
/usr/local/x86_64-pc-linux-gnu/sys-include   -g -O2  -static-libstdc++
-static-libgcc  -L ../x86_64-pc-linux-gnu/libgo -L
../x86_64-pc-linux-gnu/libgo/.libs -o cgo
../../gcc/gotools/../libgo/go/cmd/cgo/ast.go
../../gcc/gotools/../libgo/go/cmd/cgo/doc.go
../../gcc/gotools/../libgo/go/cmd/cgo/gcc.go
../../gcc/gotools/../libgo/go/cmd/cgo/godefs.go
../../gcc/gotools/../libgo/go/cmd/cgo/main.go
../../gcc/gotools/../libgo/go/cmd/cgo/out.go
../../gcc/gotools/../libgo/go/cmd/cgo/util.go zdefaultcc.go  
../../gcc/gotools/../libgo/go/cmd/go/pkg.go:370:22: error: reference to
undefined identifier âbuild.IgnoreVendorâ
   buildMode |= build.IgnoreVendor
                      ^
../../gcc/gotools/../libgo/go/cmd/go/main.go:683:81: error: reference to
undefined field or method âInvalidGoFilesâ
   if p, err := buildContext.ImportDir(path, 0); err != nil && (p == nil ||
len(p.InvalidGoFiles) == 0) {
                                                                               
 ^
Makefile:671: recipe for target 'go' failed
make[2]: *** [go] Error 1