cmd/gomobile: work around for corrupted build on Mac Catalyst

hyangah · stffabi · gopherbot · commit a87c1cf6cf46 · 2024-12-13T14:13:54.000-08:00
The problem was observed after Go 1.18. x/mobile requires go1.22.0+. Patch from stffabi@e31230f For golang/go#52299 Co-authored-by: stffabi <stffabi@users.noreply.github.com> Change-Id: I856c68f60ad7c45acf4ae550a1e66747ef7719db Reviewed-on: https://go-review.googlesource.com/c/mobile/+/635342 Auto-Submit: Hyang-Ah Hana Kim <hyangah@gmail.com> LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Ian Lance Taylor <iant@google.com>
diff --git a/cmd/gomobile/env.go b/cmd/gomobile/env.go
@@ -63,9 +63,11 @@ func platformOS(platform string) string {
 	case "macos", "maccatalyst":
 		// For "maccatalyst", Go packages should be built with GOOS=darwin,
 		// not GOOS=ios, since the underlying OS (and kernel, runtime) is macOS.
+		// But, using GOOS=darwin with build-tag ios leads to corrupt builds: https://go.dev/issue/52299
+		// => So we use GOOS=ios for now.
 		// We also apply a "macos" or "maccatalyst" build tag, respectively.
 		// See below for additional context.
-		return "darwin"
+		return "ios"
 	default:
 		panic(fmt.Sprintf("unexpected platform: %s", platform))
 	}
@@ -82,17 +84,17 @@ func platformTags(platform string) []string {
 	case "maccatalyst":
 		// Mac Catalyst is a subset of iOS APIs made available on macOS
 		// designed to ease porting apps developed for iPad to macOS.
-		// See https://developer.apple.com/mac-catalyst/.
-		// Because of this, when building a Go package targeting maccatalyst,
-		// GOOS=darwin (not ios). To bridge the gap and enable maccatalyst
-		// packages to be compiled, we also specify the "ios" build tag.
+		// See
+		//   https://developer.apple.com/mac-catalyst/.
+		//   https://stackoverflow.com/questions/12132933/preprocessor-macro-for-os-x-targets/49560690#49560690
+		//
+		// Historically gomobile used GOOS=darwin with build tag ios when
+		// targeting Mac Catalyst. However, this configuration is not officially
+		// supported and leads to corrupt builds after go1.18: https://go.dev/issues/52299
+		// Use GOOS=ios.
 		// To help discriminate between darwin, ios, macos, and maccatalyst
 		// targets, there is also a "maccatalyst" tag.
-		// Some additional context on this can be found here:
-		// https://stackoverflow.com/questions/12132933/preprocessor-macro-for-os-x-targets/49560690#49560690
-		// TODO(ydnar): remove tag "ios" when cgo supports Catalyst
-		// See golang.org/issues/47228
-		return []string{"ios", "macos", "maccatalyst"}
+		return []string{"macos", "maccatalyst"}
 	default:
 		panic(fmt.Sprintf("unexpected platform: %s", platform))
 	}
@@ -217,17 +219,11 @@ func envInit() (err error) {
 				cflags += " -mios-simulator-version-min=" + buildIOSVersion
 				cflags += " -fembed-bitcode"
 			case "maccatalyst":
-				// Mac Catalyst is a subset of iOS APIs made available on macOS
-				// designed to ease porting apps developed for iPad to macOS.
-				// See https://developer.apple.com/mac-catalyst/.
-				// Because of this, when building a Go package targeting maccatalyst,
-				// GOOS=darwin (not ios). To bridge the gap and enable maccatalyst
-				// packages to be compiled, we also specify the "ios" build tag.
-				// To help discriminate between darwin, ios, macos, and maccatalyst
-				// targets, there is also a "maccatalyst" tag.
-				// Some additional context on this can be found here:
-				// https://stackoverflow.com/questions/12132933/preprocessor-macro-for-os-x-targets/49560690#49560690
-				goos = "darwin"
+				// See the comment about maccatalyst's GOOS, build tags configuration
+				// in platformOS and platformTags.
+				// Using GOOS=darwin with build-tag ios leads to corrupt builds: https://go.dev/issue/52299
+				// => So we use GOOS=ios for now.
+				goos = "ios"
 				sdk = "macosx"
 				clang, cflags, err = envClang(sdk)
 				// TODO(ydnar): the following 3 lines MAY be needed to compile
