option for --no-lto for fuchsia (#12010)

tools/fuchsia/build_fuchsia_artifacts.py

@@ -52,6 +52,8 @@ def RunExecutable(command):
 
 
 def RunGN(variant_dir, flags):
+  print('Running gn for variant "%s" with flags: %s' % (variant_dir,
+      ','.join(flags)))
   RunExecutable([
       os.path.join('flutter', 'tools', 'gn'),
   ] + flags)
@@ -192,16 +194,19 @@ def GetTargetsToBuild(product=False):
   return targets_to_build
 
 
-def BuildTarget(runtime_mode, arch, product):
+def BuildTarget(runtime_mode, arch, product, enable_lto):
   out_dir = 'fuchsia_%s_%s' % (runtime_mode, arch)
   flags = [
       '--fuchsia',
       '--fuchsia-cpu',
       arch,
       '--runtime-mode',
-      runtime_mode
+      runtime_mode,
   ]
 
+  if not enable_lto:
+    flags.append('--no-lto')
+
   RunGN(out_dir, flags)
   BuildNinjaTargets(out_dir, GetTargetsToBuild(product))
 
@@ -228,6 +233,12 @@ def main():
       choices=['debug', 'profile', 'release', 'all'],
       default='all')
 
+  parser.add_argument(
+      '--no-lto',
+      action='store_true',
+      default=False,
+      help='If set, disables LTO for the build.')
+
   args = parser.parse_args()
   RemoveDirectoryIfExists(_bucket_directory)
   build_mode = args.runtime_mode
@@ -236,12 +247,14 @@ def main():
   runtime_modes = ['debug', 'profile', 'release']
   product_modes = [False, False, True]
 
+  enable_lto = not args.no_lto
+
   for arch in archs:
     for i in range(3):
       runtime_mode = runtime_modes[i]
       product = product_modes[i]
       if build_mode == 'all' or runtime_mode == build_mode:
-        BuildTarget(runtime_mode, arch, product)
+        BuildTarget(runtime_mode, arch, product, enable_lto)
         BuildBucket(runtime_mode, arch, product)
 
   ProcessCIPDPakcage(args.upload, args.engine_version)