cmd/internal/goobj: make the buildGoobj test helper work in module mode

Updates #30228

Change-Id: I8dd4a1f94dfd3be324a4f213941a20fa1b8b1215
Reviewed-on: https://go-review.googlesource.com/c/162832
Run-TryBot: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Jay Conrod <jayconrod@google.com>

diff --git a/src/cmd/internal/goobj/goobj_test.go b/src/cmd/internal/goobj/goobj_test.go
index 3b41589bbf1d2af56b9ae51a1d7e680a22c6135f..840b45c90885e97e5685835d665b004d31ed54f6 100644 (file)
--- a/src/cmd/internal/goobj/goobj_test.go
+++ b/src/cmd/internal/goobj/goobj_test.go
@@ -122,10 +122,14 @@ func buildGoobj() error {
        if testenv.HasCGO() {
                gopath := filepath.Join(buildDir, "gopath")
                err = copyDir(filepath.Join(gopath, "src", "mycgo"), filepath.Join("testdata", "mycgo"))
+               if err == nil {
+                       err = ioutil.WriteFile(filepath.Join(gopath, "src", "mycgo", "go.mod"), []byte("module mycgo\n"), 0666)
+               }
                if err != nil {
                        return err
                }
                cmd := exec.Command(gotool, "install", "-gcflags=all="+os.Getenv("GO_GCFLAGS"), "mycgo")
+               cmd.Dir = filepath.Join(gopath, "src", "mycgo")
                cmd.Env = append(os.Environ(), "GOPATH="+gopath)
                out, err = cmd.CombinedOutput()
                if err != nil {