1 files changed, 68 insertions, 0 deletions
diff --git a/libgo/go/cmd/internal/sys/supported.go b/libgo/go/cmd/internal/sys/supported.go
index 4162858ac1b..02f833e945e 100644
--- a/libgo/go/cmd/internal/sys/supported.go
+++ b/libgo/go/cmd/internal/sys/supported.go
@@ -43,3 +43,71 @@ func MustLinkExternal(goos, goarch string) bool {
 	}
 	return false
 }
+
+// BuildModeSupported reports whether goos/goarch supports the given build mode
+// using the given compiler.
+func BuildModeSupported(compiler, buildmode, goos, goarch string) bool {
+	if compiler == "gccgo" {
+		return true
+	}
+
+	platform := goos + "/" + goarch
+
+	switch buildmode {
+	case "archive":
+		return true
+
+	case "c-archive":
+		// TODO(bcmills): This seems dubious.
+		// Do we really support c-archive mode on js/wasm‽
+		return platform != "linux/ppc64"
+
+	case "c-shared":
+		switch platform {
+		case "linux/amd64", "linux/arm", "linux/arm64", "linux/386", "linux/ppc64le", "linux/s390x",
+			"android/amd64", "android/arm", "android/arm64", "android/386",
+			"freebsd/amd64",
+			"darwin/amd64", "darwin/386",
+			"windows/amd64", "windows/386":
+			return true
+		}
+		return false
+
+	case "default":
+		return true
+
+	case "exe":
+		return true
+
+	case "pie":
+		switch platform {
+		case "linux/386", "linux/amd64", "linux/arm", "linux/arm64", "linux/ppc64le", "linux/s390x",
+			"android/amd64", "android/arm", "android/arm64", "android/386",
+			"freebsd/amd64",
+			"darwin/amd64",
+			"aix/ppc64":
+			return true
+		}
+		return false
+
+	case "shared":
+		switch platform {
+		case "linux/386", "linux/amd64", "linux/arm", "linux/arm64", "linux/ppc64le", "linux/s390x":
+			return true
+		}
+		return false
+
+	case "plugin":
+		switch platform {
+		case "linux/amd64", "linux/arm", "linux/arm64", "linux/386", "linux/s390x", "linux/ppc64le",
+			"android/amd64", "android/arm", "android/arm64", "android/386",
+			"darwin/amd64",
+			"freebsd/amd64":
+			return true
+		}
+		return false
+
+	default:
+		return false
+	}
+}