support CC/CXX per-target

go.go

@@ -26,6 +26,8 @@ type CompileOpts struct {
 	OutputTpl   string
 	Ldflags     string
 	Gcflags     string
+	Cc          string
+	Cxx         string
 	Asmflags    string
 	Tags        string
 	Cgo         bool
@@ -39,6 +41,13 @@ func GoCrossCompile(opts *CompileOpts) error {
 		"GOOS="+opts.Platform.OS,
 		"GOARCH="+opts.Platform.Arch)
 
+	if opts.Cc != "" {
+		env = append(env, "CC="+opts.Cc)
+	}
+	if opts.Cxx != "" {
+		env = append(env, "CXX="+opts.Cxx)
+	}
+
 	// If we're building for our own platform, then enable cgo always. We
 	// respect the CGO_ENABLED flag if that is explicitly set on the platform.
 	if !opts.Cgo && os.Getenv("CGO_ENABLED") != "0" {

main.go

@@ -143,6 +143,8 @@ func realMain() int {
 				envOverride(&opts.Ldflags, platform, "LDFLAGS")
 				envOverride(&opts.Gcflags, platform, "GCFLAGS")
 				envOverride(&opts.Asmflags, platform, "ASMFLAGS")
+				envOverride(&opts.Cc, platform, "CC")
+				envOverride(&opts.Cxx, platform, "CXX")
 
 				if err := GoCrossCompile(opts); err != nil {
 					errorLock.Lock()