What version of Go are you using (go version)?

This happens with any version from go version devel +b7c600d Mon Aug 14 18:45:21 2017 +0000 linux/amd64 onward, and reproduces in the current git tip go version devel +9c9df65.

What operating system and processor architecture are you using (go env)?

GOARCH="amd64"
GOOS="linux"

What did you do?

If you have a git clone of the Go tree on amd64 Linux, you update the tree with eg 'git pull', and you attempt to rebuild without removing linux_amd64_shared/runtime/cgo.a, you'll get a failure during TestBuildmodePIE:

--- FAIL: TestBuildmodePIE (1.19s)
        go_test.go:312: running testgo [build -buildmode=pie -o /tmpfs/gotest561625280/main /tmpfs/gotest561625280/main.go]
        go_test.go:325: standard error:
        go_test.go:326: # command-line-arguments
                /tmp/go/pkg/linux_amd64_shared/runtime/cgo.a(_go_.o): object is [linux amd64 devel +25b040c Wed Aug 16 10:07:47 2017 +0000 X:framepointer] expected [linux amd64 devel +b26ad60 Wed Aug 16 15:30:35 2017 +0000 ]
                /tmp/go/pkg/linux_amd64_shared/runtime/cgo.a(asm_amd64.o): object is [linux amd64 devel +25b040c Wed Aug 16 10:07:47 2017 +0000] expected [linux amd64 devel +b26ad60 Wed Aug 16 15:30:35 2017 +0000 ]

        go_test.go:335: go [build -buildmode=pie -o /tmpfs/gotest561625280/main /tmpfs/gotest561625280/main.go] failed unexpectedly: exit status 2
FAIL
FAIL    cmd/go  40.721s

A typical reproduction on a system with a /usr/bin/go is:

• clone the git repo into /tmp: cd /tmp; git clone https://go.googlesource.com/go
• set up to build: export GOROOT_BOOTSTRAP=$(/usr/bin/go env GOROOT)
• step back a version or two: cd go; git checkout 25b040c
• build and test that version: cd src; ./all.bash
• check out the current version: git checkout master
• try to build and test the current version: ./all.bash

The last step will fail. Removing the cgo.a file and retrying the ./all.bash will cause the build to succeed.

My testing says that this was introduced in commit b7c600d, 'cmd/go, cmd/link: enable buildmode=pie on darwin/amd64', intended to fix #21220. This commit is where TestBuildmodePIE is added.