Fix gyptest-xcode-gcc.py when using Xcode 5.0.2

test/mac/gyptest-xcode-gcc.py

 #!/usr/bin/env python
 
 # Copyright (c) 2012 Google Inc. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """
 Verifies that xcode-style GCC_... settings are handled properly.
 """
 
 import TestGyp
 
 import os
+import subprocess
 import sys
 
 def IgnoreOutput(string, expected_string):
   return True
 
+def CompilerVersion(compiler):
+  stdout = subprocess.check_output([compiler, '-v'], stderr=subprocess.STDOUT)
+  return stdout.rstrip('\n')
+
+def CompilerSupportsWarnAboutInvalidOffsetOfMacro(test):
+  # With Xcode 5.0.2, gcc is a version of clang using different binary and
+  # include directories. It then behaves like clang and doesn't warn on
+  # invalid offsetofs (it silently ignore -Wno-invalid-offsetof).
+  if 'clang' in CompilerVersion('/usr/bin/gcc'):
+    return False
+  # TODO(thakis): This isn't really the right way to detect the compiler,
+  # Xcode has some embedded compiler, but it's a reliable proxy at least on
+  # the bots. The compiler is forced to gcc/g++ in the gyp file in a
+  # make_global_settings section for ninja and make.
+  return test.format != 'xcode' or os.readlink('/usr/bin/cc') != 'clang'

[Mark Mentovai, 2013/12/06 20:17:56]

I think that testing |'clang' in CompilerVersion('/usr/bin/gcc')| is a better
version of the os.readlink test, because it should detect both symbolic link and
non-symbolic-link installations of cc (or gcc) as clang. Can you simplify this
function?

[sdefresne, 2013/12/10 12:38:43]

Done.

+
 if sys.platform == 'darwin':
   test = TestGyp.TestGyp(formats=['ninja', 'make', 'xcode'])
 
   CHDIR = 'xcode-gcc'
   test.run_gyp('test.gyp', chdir=CHDIR)
 
   # List of targets that'll pass. It expects targets of the same name with
   # '-fail' appended that'll fail to build.
   targets = [
     'warn_about_missing_newline',
   ]
 
   # clang doesn't warn on invalid offsetofs, it silently ignores
   # -Wno-invalid-offsetof.
-  # TODO(thakis): This isn't really the right way to detect the compiler,
-  # Xcode has some embedded compiler, but it's a reliable proxy at least on
-  # the bots. The compiler is forced to gcc/g++ in the gyp file in a
-  # make_global_settings section for ninja and make.
-  if test.format != 'xcode' or os.readlink('/usr/bin/cc') != 'clang':
+  if CompilerSupportsWarnAboutInvalidOffsetOfMacro(test):
     targets.append('warn_about_invalid_offsetof_macro')
 
   for target in targets:
     test.build('test.gyp', target, chdir=CHDIR)
     test.built_file_must_exist(target, chdir=CHDIR)
     fail_target = target + '-fail'
     test.build('test.gyp', fail_target, chdir=CHDIR, status=None,
                stderr=None, match=IgnoreOutput)
     test.built_file_must_not_exist(fail_target, chdir=CHDIR)
 
   test.pass_test()