flutter · auto-submit · Apr 26, 2025 · Mar 8, 2025 · Apr 22, 2025 · Apr 22, 2025
diff --git a/engine/src/build/config/apple/apple_sdk.gni b/engine/src/build/config/apple/apple_sdk.gni
@@ -0,0 +1,17 @@
+# Copyright 2013 The Flutter Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+declare_args() {
+  # Path to the Xcode toolchain (XcodeDefault.xctoolchain).
+  apple_host_toolchain_path = ""
+}
+
+if (apple_host_toolchain_path == "") {
+  # Outputs the SDK path on the first line, and the host toolchain path on the
+  # second.
+  _find_sdk_lines =
+      exec_script("//build/mac/find_sdk.py", ["--print_sdk_path", "1.0"], "list lines")
+
+  apple_host_toolchain_path = _find_sdk_lines[1]
+}
diff --git a/engine/src/build/config/compiler/BUILD.gn b/engine/src/build/config/compiler/BUILD.gn
@@ -66,8 +66,15 @@ config("compiler") {
   cflags_c = []
   cflags_cc = []
   cflags_objcc = []
+  swiftflags = []
   ldflags = []
   defines = []
+  configs = []
+
+  # Platform-specific configs.
+  if (is_ios) {
+    configs += [ "//build/config/ios:compiler" ]
+  }
 
   # In general, Windows is totally different, but all the other builds share
   # some common GCC configuration. This section sets up Windows and the common
@@ -534,17 +541,26 @@ config("runtime_library") {
   }
 
   if (use_flutter_cxx) {
-    cflags_cc += [ "-nostdinc++" ]
-    cflags_objcc += [ "-nostdinc++" ]
+    # Add libcxx[abi]/include via cflags_cc, cflags_objcc to apply to
+    # C++/Obj-C++ only. Adding them via include_dirs is problematic for Swift,
+    # whose core libraries expect the Apple SDK C++ headers, module.modulemap.
+    _libcxx_include = rebase_path("//flutter/third_party/libcxx/include", root_build_dir)
+    _libcxxabi_include = rebase_path("//flutter/third_party/libcxxabi/include", root_build_dir)
+    cflags_cc += [
+      "-nostdinc++",
+      "-I" + _libcxx_include,
+      "-I" + _libcxxabi_include,
+    ]
+    cflags_objcc += [
+      "-nostdinc++",
+      "-I" + _libcxx_include,
+      "-I" + _libcxxabi_include,
+    ]
 
     # Unwind seemes to be in these libraries in Linux.
     if (!is_linux) {
       ldflags += [ "-nostdlib++" ]
     }
-    include_dirs = [
-      "//flutter/third_party/libcxx/include",
-      "//flutter/third_party/libcxxabi/include",
-    ]
   }
 
   # Android standard library setup.
@@ -991,6 +1007,9 @@ config("symbols") {
     }
   } else {
     cflags = [ "-g2" ]
+    if (is_apple) {
+      swiftflags = [ "-g" ]
+    }
   }
 }
 

@@ -6,6 +6,66 @@ config("sdk") {
   cflags_cc = [ "-stdlib=libc++" ]
 }
 
+config("compiler") {
+  # swiftc -sdk flag.
+  _sdk_root = ios_sdk_path
+  if (create_xcode_symlinks) {
+    _sdk_root = rebase_path(ios_sdk_path, root_build_dir)
+  }
+
+  # swiftc -target flag (target triplet).
+  # CPU architecture.
+  if (current_cpu == "x64") {
+    _triplet_cpu = "x86_64"
+  } else if (current_cpu == "arm64") {
+    _triplet_cpu = "arm64"
+  } else {
+    # x86, arm, armv7, etc.
+    assert(false, "unsupported cpu: $current_cpu")
+  }
+  # Environment.
+  if (use_ios_simulator) {
+    _triplet_environment = "-simulator"
+  } else {
+    _triplet_environment = ""
+  }
+  # OS.
+  if (is_ios) {
+    _triplet_os = "apple-ios"
+  } else if (is_mac) {
+    _triplet_os = "apple-macos"
+  } else {
+    assert(false, "unsupported Apple os")
+  }
+  _target_triplet = "$_triplet_cpu-$_triplet_os$ios_deployment_target$_triplet_environment"
+
+  # swiftc -swift-version flag.
+  #
+  # Swift 6 transition: As of April 2025, no public Flutter framework API is
+  # authored in Swift. Swift 6 is ABI-compatible with Swift 5, but not
+  # source-compatible. If any public API *is* written in Swift, it's possible
+  # we may need to prepare concurrent Swift 5 and 6 builds during a transition
+  # period.
+  _swift_version = "5"
+
+  # TODO(cbracken): https://github.com/flutter/flutter/issues/167592
+  # Look up xcode_version in ios_sdk.gni/mac_sdk.gni.
+  #
+  # This is here so that all files get recompiled after an Xcode update.
+  # (defines are passed via the command line, and build system rebuild things
+  # when their commandline changes). Nothing should ever read this define.
+  #defines = [ "CR_XCODE_VERSION=$xcode_version" ]
+
+  swiftflags = [
+    "-sdk",
+    _sdk_root,
+    "-target",
+    _target_triplet,
+    "-swift-version",
+    _swift_version
+  ]
+}
+
 config("ios_application_extension") {
   cflags_objc = [ "-fapplication-extension" ]
   cflags_objcc = [ "-fapplication-extension" ]

@@ -1,7 +1,8 @@
-# Copyright 2015 The Chromium Authors. All rights reserved.
+# Copyright 2013 The Flutter Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
+import("//build/config/apple/apple_sdk.gni")
 import("//build/toolchain/rbe.gni")
 
 declare_args() {
@@ -27,6 +28,9 @@ declare_args() {
   # The path to the iOS simulator SDK.
   ios_simulator_sdk_path = ""
 
+  # The path to iOS SDK Swift libraries.
+  ios_swift_lib_paths = []
+
   # Version of iOS that we're targeting for tests.
   ios_testing_deployment_target = "13.0"
 }
@@ -66,3 +70,15 @@ if (ios_sdk_path == "") {
     ios_sdk_path = ios_device_sdk_path
   }
 }
+
+# Set in //build/config/apple/apple_sdk.gni.
+assert (apple_host_toolchain_path != "")
+
+if (ios_swift_lib_paths == []) {
+  ios_swift_lib_paths += [rebase_path("$ios_sdk_path/usr/lib/swift")]
+  if (use_ios_simulator) {
+    ios_swift_lib_paths += [rebase_path("$apple_host_toolchain_path/usr/lib/swift/iphonesimulator")]
+  } else {
+    ios_swift_lib_paths += [rebase_path("$apple_host_toolchain_path/usr/lib/swift/iphoneos")]
+  }
+}
@@ -1,4 +1,4 @@
-# Copyright 2014 The Chromium Authors. All rights reserved.
+# Copyright 2013 The Flutter Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 

diff --git a/engine/src/build/config/mac/mac_sdk.gni b/engine/src/build/config/mac/mac_sdk.gni
@@ -1,7 +1,8 @@
-# Copyright 2014 The Chromium Authors. All rights reserved.
+# Copyright 2013 The Flutter Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
+import("//build/config/apple/apple_sdk.gni")
 import("//build/toolchain/rbe.gni")
 
 declare_args() {
@@ -35,10 +36,10 @@ if (mac_sdk_path == "") {
     mac_sdk_min,
   ]
 
-  # The tool will print the SDK path on the first line, and the version on the
-  # second line.
-  find_sdk_lines =
+  # Outputs the SDK path on the first line, and the host toolchain path on the
+  # second.
+  _find_sdk_lines =
       exec_script("//build/mac/find_sdk.py", find_sdk_args, "list lines")
 
-  mac_sdk_path = find_sdk_lines[0]
+  mac_sdk_path = _find_sdk_lines[0]
 }
diff --git a/engine/src/build/mac/find_sdk.py b/engine/src/build/mac/find_sdk.py
@@ -1,6 +1,6 @@
 #!/usr/bin/env python3
 #
-# Copyright (c) 2012 The Chromium Authors. All rights reserved.
+# Copyright 2013 The Flutter Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
@@ -91,7 +91,11 @@ def main():
       '|sudo xcode-select --switch /Applications/Xcode.app/Contents/Developer| '
       'if you are using Xcode 4.') % job.returncode)
 
-  # xcrun --sdk macosx  --show-sdk-path
+  # Locate the host toolchain.
+  xcode_dir = run_command_with_retry(['xcode-select', '-print-path'], timeout=300)
+  toolchain_dir = os.path.join(xcode_dir, 'Toolchains/XcodeDefault.xctoolchain')
+
+  # Locate the target SDK.
   sdk_command = [
     'xcrun',
     '--sdk',
@@ -101,12 +105,17 @@ def main():
   sdk_output = run_command_with_retry(sdk_command, timeout=300)
   if symlink_path:
     sdks_path = os.path.join(symlink_path, 'SDKs')
+    # Symlink the host toolchain.
+    toolchain_target = os.path.join(sdks_path, 'XcodeDefault.xctoolchain')
+    symlink(toolchain_dir, toolchain_target)
+    # Symlink the SDK.
     symlink_target = os.path.join(sdks_path, os.path.basename(sdk_output))
     symlink(sdk_output, symlink_target)
     sdk_output = symlink_target
 
   if not options.as_gclient_hook:
     print(sdk_output)
+    print(toolchain_dir)
   return 0
 
 

diff --git a/engine/src/build/toolchain/apple/get_tool_mtime.py b/engine/src/build/toolchain/apple/get_tool_mtime.py
@@ -0,0 +1,20 @@
+#!/usr/bin/env python3
+#
+# Copyright 2013 The Flutter Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+
+import os
+import sys
+
+# Usage: python get_tool_mtime.py path/to/file1.py path/to/file2.py
+#
+# Prints a GN scope with the variable name being the basename sans-extension
+# and the value being the file modification time. A variable is emitted for
+# each file argument on the command line.
+
+if __name__ == '__main__':
+  for f in sys.argv[1:]:
+    variable = os.path.splitext(os.path.basename(f))[0]
+    print('%s = %d' % (variable, os.path.getmtime(f)))
diff --git a/engine/src/build/toolchain/apple/swift_const_gather_protocols.json b/engine/src/build/toolchain/apple/swift_const_gather_protocols.json
@@ -0,0 +1 @@
+["AppIntent","EntityQuery","AppEntity","TransientEntity","AppEnum","AppShortcutProviding","AppShortcutsProvider","AnyResolverProviding","AppIntentsPackage","DynamicOptionsProvider"]
Original file line number	Diff line number	Diff line change
		@@ -0,0 +1 @@
		["AppIntent","EntityQuery","AppEntity","TransientEntity","AppEnum","AppShortcutProviding","AppShortcutsProvider","AnyResolverProviding","AppIntentsPackage","DynamicOptionsProvider"]