cmd/link: Unable to cross-compile darwin/amd64 PIE on Linux

[Matir]

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

$ go version
go version go1.13.4 linux/amd64

Does this issue reproduce with the latest release?

Yes

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

go env Output

$ go env
GO111MODULE=""
GOARCH="amd64"
GOBIN=""
GOCACHE="/home/matir/.cache/go-build"
GOENV="/home/matir/.config/go/env"
GOEXE=""
GOFLAGS=""
GOHOSTARCH="amd64"
GOHOSTOS="linux"
GONOPROXY=""
GONOSUMDB=""
GOOS="linux"
GOPATH="/home/matir/Projects/Go:/usr/share/gocode"
GOPRIVATE=""
GOPROXY="https://proxy.golang.org,direct"
GOROOT="/home/matir/tmp/repro/go"
GOSUMDB="sum.golang.org"
GOTMPDIR=""
GOTOOLDIR="/home/matir/tmp/repro/go/pkg/tool/linux_amd64"
GCCGO="gccgo"
AR="ar"
CC="gcc"
CXX="g++"
CGO_ENABLED="1"
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 -m64 -pthread -fmessage-length=0 -fdebug-prefix-map=/tmp/go-build817158144=/tmp/go-build -gno-record-gcc-switches"

What did you do?

$ cat test.go                                                                                                          ✘ 2 
package main

import "fmt"

func main() {
	fmt.Println("Hello world!")
}

GOOS=darwin ./go/bin/go build -buildmode=pie -ldflags="-v" ./test.go
# command-line-arguments
HEADER = -H1 -T0x1001000 -R0x1000
 0.00 deadcode
 0.01 symsize = 0
 0.03 pclntab=481762 bytes, funcdata total 114944 bytes
 0.04 dodata
 0.04 symsize = 0
 0.04 symsize = 0
 0.04 dynreloc
 0.04 dwarf
 0.06 asmb
 0.06 codeblk
 0.08 datblk
 0.10 reloc
 0.13 sym
 0.13 headr
 0.19 host link: "gcc" "-m64" "-Wl,-headerpad,1144" "-o" "/tmp/go-build300671719/b001/exe/a.out" "-Wl,--compress-debug-sections=zlib-gnu" "/tmp/go-link-648714504/go.o"
/home/matir/tmp/repro/go/pkg/tool/linux_amd64/link: running gcc failed: exit status 1
/usr/bin/ld: cannot find 1144: No such file or directory
/tmp/go-link-648714504/go.o: file not recognized: file format not recognized
collect2: error: ld returned 1 exit status

What did you expect to see?

A successful build of test.go for Darwin.

What did you see instead?

A failed build due to passing a mac-only flag to gcc on a native host.

[ianlancetaylor]

In order to cross-build a PIE from GNU/Linux to Darwin, you must set CC to a Darwin C cross-compiler, which will need to be able to see a set of Darwin libraries.