x/sys: go build fail on powerPC64 using gccgo

[wj36604]

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

$ go version
go version go1.12.2 gccgo (GCC) 9.1.0 linux/ppc64

Does this issue reproduce with the latest release?

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

go env Output

$ go env
GOARCH="ppc64"
GOBIN=""
GOCACHE="/root/.cache/go-build"
GOEXE=""
GOFLAGS=""
GOHOSTARCH="ppc64"
GOHOSTOS="linux"
GOOS="linux"
GOPATH="/opt/golang"
GOPROXY=""
GORACE=""
GOROOT="/opt/gcc-9.1.0"
GOTMPDIR=""
GOTOOLDIR="/opt/gcc-9.1.0/libexec/gcc/powerpc64-unknown-linux-gnu/9.1.0"
GCCGO="/opt/gcc-9.1.0/bin/gccgo"
CC="gcc"
CXX="g++"
CGO_ENABLED="0"
GOMOD=""
CGO_CFLAGS="-g -O2"
CGO_CPPFLAGS=""
CGO_CXXFLAGS="-g -O2"
CGO_FFLAGS="-g -O2"
CGO_LDFLAGS="-g -O2"
PKG_CONFIG="pkg-config"
GOGCCFLAGS="-fPIC -fmessage-length=0 -fdebug-prefix-map=/tmp/go-build451740613=/tmp/go-build -gno-record-gcc-switches -funwind-tables"

What did you do?

cat /proc/version
Linux version 4.1.35-g2019-05-20-637432e (houzp@dev) (gcc version 4.9.2 (GCC) ) #118 SMP Mon May 20 12:59:31 CST 2019

go build

What did you expect to see?

compile success

What did you see instead?

usb_client

/root/.cache/go-build/09/09c966f52bbded84a8ec71e8ff39f8486d6c851665f52cc7420a13ecb26bdaf5-d(go.o): In function unix.realSyscallNoError': /opt/golang/src/usb_client/vendor/golang.org/x/sys/unix/gccgo.go:22: undefined reference to gccgoRealSyscall'
/root/.cache/go-build/09/09c966f52bbded84a8ec71e8ff39f8486d6c851665f52cc7420a13ecb26bdaf5-d(go.o): In function usb_client..z2fvendor..z2fgolang.org..z2fx..z2fsys..z2funix.RawSyscallNoError': affinity_linux.go:(.text+0x6168): undefined reference to gccgoRealSyscall'
/root/.cache/go-build/09/09c966f52bbded84a8ec71e8ff39f8486d6c851665f52cc7420a13ecb26bdaf5-d(go.o): In function usb_client..z2fvendor..z2fgolang.org..z2fx..z2fsys..z2funix.Syscall': affinity_linux.go:(.text+0x6498): undefined reference to gccgoRealSyscall'
/root/.cache/go-build/09/09c966f52bbded84a8ec71e8ff39f8486d6c851665f52cc7420a13ecb26bdaf5-d(go.o): In function usb_client..z2fvendor..z2fgolang.org..z2fx..z2fsys..z2funix.Syscall6': affinity_linux.go:(.text+0x6704): undefined reference to gccgoRealSyscall'
/root/.cache/go-build/09/09c966f52bbded84a8ec71e8ff39f8486d6c851665f52cc7420a13ecb26bdaf5-d(go.o): In function usb_client..z2fvendor..z2fgolang.org..z2fx..z2fsys..z2funix.Syscall9': affinity_linux.go:(.text+0x68c8): undefined reference to gccgoRealSyscall'
/root/.cache/go-build/09/09c966f52bbded84a8ec71e8ff39f8486d6c851665f52cc7420a13ecb26bdaf5-d(go.o):affinity_linux.go:(.text+0x6958): more undefined references to `gccgoRealSyscall' follow
collect2: error: ld returned 1 exit status

[ianlancetaylor]

This looks like a problem with usb_client, not with x/sys. You are building a vendored version of golang.org/x/sys/unix. You didn't say which version is vendored. The first thing to try is updating to the current version of golang.org/x/sys/unix.

[wj36604]

I'm sorry for the late reply firstly. If go build on powerPC64 will use gccgo?
When the a package is not used in the program，go build success and the program is running normally.

[ianlancetaylor]

If you use the go tool that is distributed with gccgo, then running go build will use gccgo.

If you use the go tool that is distributed with the gc toolchain, which is the version that you can fetch from https://golang.org, then running go build will not use gccgo.

In the comment above you are using the go tool that is distributed with gccgo. I can tell because the output of go version says "gccgo".

[wj36604]

Thanks for your reply.There is a problem with the "gccgo" compilation environment.
Compiling on another host is fine, will reinstall the build tool。

[ianlancetaylor]

Thanks for following up.