build: TestBuildmodePIE failed on linux

[choleraehyq]

Please answer these questions before submitting your issue. Thanks!

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

use go 1.9 rc2 to compile go tip 58cb8a3c8fdc9b83cb8630f17d0ee641eb0327cc

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

GOARCH="amd64"
GOBIN=""
GOEXE=""
GOHOSTARCH="amd64"
GOHOSTOS="linux"
GOOS="linux"
GOPATH="/home/cholerae/gopath"
GORACE=""
GOROOT="/home/cholerae/gopath/go"
GOTOOLDIR="/home/cholerae/gopath/go/pkg/tool/linux_amd64"
GCCGO="gccgo"
CC="gcc"
GOGCCFLAGS="-fPIC -m64 -pthread -fmessage-length=0 -fdebug-prefix-map=/tmp/go-build447838512=/tmp/go-build -gno-record-gcc-switches"
CXX="g++"
CGO_ENABLED="1"
CGO_CFLAGS="-g -O2"
CGO_CPPFLAGS=""
CGO_CXXFLAGS="-g -O2"
CGO_FFLAGS="-g -O2"
CGO_LDFLAGS="-g -O2"
PKG_CONFIG="pkg-config"

What did you do?

If possible, provide a recipe for reproducing the error.
A complete runnable program is good.
A link on play.golang.org is best.
GOROOT_BOOTSTRAP=/home/cholerae/gopath/go ./all.bash

What did you expect to see?

all tests passed.

What did you see instead?

--- FAIL: TestBuildmodePIE (2.15s)
	go_test.go:312: running testgo [build -buildmode=pie -o /tmp/gotest833919002/main /tmp/gotest833919002/main.go]
	go_test.go:325: standard error:
	go_test.go:326: # command-line-arguments
		/home/cholerae/test/go/pkg/linux_amd64_shared/runtime/cgo.a(_go_.o): object is [linux amd64 devel +adc28cb1e0 Fri Aug 11 18:00:53 2017 +0000 X:framepointer] expected [linux amd64 devel +58cb8a3c8f Tue Aug 15 07:19:25 2017 +0000 ]
		/home/cholerae/test/go/pkg/linux_amd64_shared/runtime/cgo.a(asm_amd64.o): object is [linux amd64 devel +adc28cb1e0 Fri Aug 11 18:00:53 2017 +0000] expected [linux amd64 devel +58cb8a3c8f Tue Aug 15 07:19:25 2017 +0000 ]
		
	go_test.go:335: go [build -buildmode=pie -o /tmp/gotest833919002/main /tmp/gotest833919002/main.go] failed unexpectedly: exit status 2
FAIL
FAIL	cmd/go	67.917s

[ALTree]

Same on my linux/amd64 system.

I bisected this to b7c600d

cc @hirochachacha @ianlancetaylor

[hirochachacha]

I didn't change anything about Linux.
Could you compile a trivial program with buildmode=pie ?
e.g.

$ cat main.go
package main; func main() { print("hello") }
$ go build -buildmode=pie -o main main.go

Thank you.

[ALTree]

$ cat test.go
package main

func main() {
	print("hello")
}

$ gotip version
go version devel +583a941d4e Tue Aug 15 10:10:42 2017 +0000 linux/amd64

$ gotip build -buildmode=pie test.go
# command-line-arguments
/home/alberto/go/pkg/linux_amd64_shared/runtime/cgo.a(_go_.o): object is [linux amd64 devel +ae24c167c7 Mon Aug 14 14:52:00 2017 +0200 X:framepointer] expected [linux amd64 devel +583a941d4e Tue Aug 15 10:10:42 2017 +0000 ]
/home/alberto/go/pkg/linux_amd64_shared/runtime/cgo.a(asm_amd64.o): object is [linux amd64 devel +ae24c167c7 Mon Aug 14 14:52:00 2017 +0200] expected [linux amd64 devel +583a941d4e Tue Aug 15 10:10:42 2017 +0000 ]

Ah, it bisected to your change because that's the one that added that PIE test... but -buildmode=pie was already broken. I checked out the commit before yours and it gives the same error.

[hirochachacha]

I see. It seems the compiler should recompile dependent packages if it is necessary, instead of error. I don't know where that logic is defined though.

[hirochachacha]

Anyway, thank you for your confirmation.

[ALTree]

Cleaning out manually the old pkgs works as a workaround to fix all.bash. Anyway it would be nice if the toolchain could figure this out by itself.

[ianlancetaylor]

I think this is basically a bug in cmd/go: it doesn't take relevant flag settings into account when deciding whether it needs to rebuild a package.

Until cmd/go is fixed we can fixed TestBuildmodePIE by using an -installsuffix option in the test.

[jessfraz]

I can fix the test

[gopherbot]

Change https://golang.org/cl/55812 mentions this issue: cmd/go: add -installsuffix to TestBuildmodePIE

[ianlancetaylor]

I see the problem, it's in cmd/go. Will send a CL.

[gopherbot]

Change https://golang.org/cl/57231 mentions this issue: cmd/go: -buildmode=pie forces external linking mode on all systems