cmd/link: panic during go install -buildmode=shared -linkshared std

[paulzhol]

1. What version of Go are you using (go version)?
   go version devel +80a0517 Tue Mar 15 16:25:40 2016 +0000 linux/386
2. What operating system and processor architecture are you using (go env)?

GOARCH="386"
GOBIN=""
GOEXE=""
GOHOSTARCH="386"
GOHOSTOS="linux"
GOOS="linux"
GOPATH=""
GORACE=""
GOROOT="/home/yuval/go.git"
GOTOOLDIR="/home/yuval/go.git/pkg/tool/linux_386"
CC="gcc"
GOGCCFLAGS="-fPIC -m32 -pthread -fmessage-length=0 -fdebug-prefix-map=/tmp/go-build105912400=/tmp/go-build -gno-record-gcc-switches"
CXX="g++"
CGO_ENABLED="1"

1. What did you do?
   running GOHOSTARCH=386 GOARCH=386 ../bin/go install -buildmode=shared -linkshared std
   from the src directory.
2. What did you expect to see?
   success
3. What did you see instead?

# /tmp/go-build111140044/libstd.so
panic: method slice pointer in ".dup" leads to a different symbol

goroutine 1 [running]:
panic(0x81d5080, 0x1e9e2bf0)
        /home/yuval/go.git/src/runtime/panic.go:500 +0x331
cmd/link/internal/ld.decodetype_methods(0x1cdb1b50, 0x0, 0x0, 0x0)
        /home/yuval/go.git/src/cmd/link/internal/ld/decodesym.go:351 +0x31d
cmd/link/internal/ld.(*deadcodepass).flood(0x1853bd94)
        /home/yuval/go.git/src/cmd/link/internal/ld/deadcode.go:306 +0x998
cmd/link/internal/ld.deadcode(0x18796000)
        /home/yuval/go.git/src/cmd/link/internal/ld/deadcode.go:59 +0x1ae
cmd/link/internal/ld.Ldmain()
        /home/yuval/go.git/src/cmd/link/internal/ld/pobj.go:190 +0x1290
cmd/link/internal/x86.Main()
        /home/yuval/go.git/src/cmd/link/internal/x86/obj.go:44 +0x1c
main.main()
        /home/yuval/go.git/src/cmd/link/main.go:25 +0xf6

[ianlancetaylor]

CC @mwhudson

[mwhudson]

Hm happens on linux/amd64 too. Oh good.

[gopherbot]

CL https://golang.org/cl/20780 mentions this issue.