cmd/go: invalid flag in #cgo CFLAGS: -F

[zyxkad]

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

$ go version
go version go1.17.2 darwin/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="on"
GOARCH="amd64"
GOBIN="**"
GOCACHE="**"
GOENV="**"
GOEXE=""
GOEXPERIMENT=""
GOFLAGS=""
GOHOSTARCH="amd64"
GOHOSTOS="darwin"
GOINSECURE=""
GOMODCACHE="**"
GONOPROXY="yes"
GONOSUMDB=""
GOOS="darwin"
GOPATH="**"
GOPRIVATE=""
GOPROXY="https://proxy.golang.org,direct"
GOROOT="/usr/local/go"
GOSUMDB="sum.golang.org"
GOTMPDIR=""
GOTOOLDIR="/usr/local/go/pkg/tool/darwin_amd64"
GOVCS=""
GOVERSION="go1.17.2"
GCCGO="gccgo"
AR="ar"
CC="clang"
CXX="clang++"
CGO_ENABLED="1"
GOMOD=""
CGO_CFLAGS="-g -O2 -std=c17"
CGO_CPPFLAGS=""
CGO_CXXFLAGS="-g -O2 -std=c++17"
CGO_FFLAGS="-g -O2"
CGO_LDFLAGS="-g -O2"
PKG_CONFIG="pkg-config"
GOGCCFLAGS="-fPIC -arch x86_64 -m64 -pthread -fno-caret-diagnostics -Qunused-arguments -fmessage-length=0 -fdebug-prefix-map=/var/folders/fh/sxp5v53x66j5_p6_9rxtx6b80000gp/T/go-build2886836689=/tmp/go-build -gno-record-gcc-switches -fno-common"

What did you do?

package my_cgo

//#cgo CFLAGS: -F /usr/local/my_framework/lib -framework MyFramework
//#cgo LDFLAGS: -F /usr/local/my_framework/lib -framework MyFramework
//
//#include <MyFramework/somefile.h>
import "C"

What did you expect to see?

Success

What did you see instead?

go build xxx/xxx/xxx: invalid flag in #cgo CFLAGS: -F
[Finished in 458ms with exit code 1]

---

The option -F is actually in clang

$ clang --help | grep '\-F'
 -F <value>              Add directory to framework include search path
$ clang++ --help | grep '\-F'
 -F <value>              Add directory to framework include search path

[ianlancetaylor]

Was that the complete error message? With Go 1.17 the error message should have mentioned https://golang.org/s/invalidflag, which explains how you can work around the problem.

[zyxkad]

Yes that's all, but it don't tell me https://golang.org/s/invalidflag

[zyxkad]

I was running go test -v ${file}, and I got the error

[zyxkad]

I was trying CGO_CFLAGS_ALLOW, but it dosen't work

$ go env -w CGO_CFLAGS_ALLOW="-F"; echo $?
0
$ go env CGO_CFLAGS_ALLOW
[[GOT EMPTY]]

[bcmills]

@zyxkad, do you have CGO_CFLAGS_ALLOW explicitly set in your process environment? A value in the environment always overrides the value in the go.env file.

[ianlancetaylor]

From the code it looks like -F/usr/local/my_framework/lib will work without any environment variable setting, but we didn't consider the case of -F /usr/local/my_framework/lib (with a space after the -F).

[gopherbot]

Change https://golang.org/cl/383217 mentions this issue: cmd/go: accept "-F dir" in compiler flags

[zyxkad]

@zyxkad, do you have CGO_CFLAGS_ALLOW explicitly set in your process environment? A value in the environment always overrides the value in the go.env file.

No, I wasn't, I also try export CGO_CFLAGS_ALLOW="-F"
but it always return to me nothing

[zyxkad]

From the code it looks like -F/usr/local/my_framework/lib will work without any environment variable setting, but we didn't consider the case of -F /usr/local/my_framework/lib (with a space after the -F).

Yes, that's work for me, thanks