mac: Support ARCHS with zero or one element in the make and ninja generators.

pylib/gyp/xcode_emulation.py

 # 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.
 
 """
 This module contains classes that help to emulate xcodebuild behavior on top of
 other build systems, such as make and ninja.
 """
 
 import gyp.common
@@ skipping 259 matching lines @@
 
     if self._Test('GCC_TREAT_WARNINGS_AS_ERRORS', 'YES', default='NO'):
       cflags.append('-Werror')
 
     if self._Test('GCC_WARN_ABOUT_MISSING_NEWLINE', 'YES', default='NO'):
       cflags.append('-Wnewline-eof')
 
     self._Appendf(cflags, 'MACOSX_DEPLOYMENT_TARGET', '-mmacosx-version-min=%s')
 
     # TODO:
-    self._WarnUnimplemented('ARCHS')
     if self._Test('COPY_PHASE_STRIP', 'YES', default='NO'):
       self._WarnUnimplemented('COPY_PHASE_STRIP')
     self._WarnUnimplemented('GCC_DEBUGGING_SYMBOLS')
     self._WarnUnimplemented('GCC_ENABLE_OBJC_EXCEPTIONS')
     self._WarnUnimplemented('GCC_ENABLE_OBJC_GC')
 
     # TODO: This is exported correctly, but assigning to it is not supported.
     self._WarnUnimplemented('MACH_O_TYPE')
     self._WarnUnimplemented('PRODUCT_TYPE')
 
-    # TODO: Do not hardcode arch. Supporting fat binaries will be annoying.
-    # Even if self._Settings()['ARCHS'] contains only a single arch, dependent
-    # targets might have been built with a different single arch.
-    cflags.append('-arch i386')
+    archs = self._Settings().get('ARCHS', ['i386'])
+    if len(archs) == 0:
+      pass

[Nico, 2012/02/13 06:09:07]

I believe xcodebuild might default to i386 if ARCHS is empty.

+    elif len(archs) == 1:
+      cflags.append('-arch ' + archs[0])

[Nico, 2012/02/13 06:09:07]

What if you have this setup:

{
  'targets': [
  {
    'target_name': 'lib',
    'type': 'static_library',
    'sources': 'my_file.cc',
    # Note: No ARCHS, which (I think) means i386
  },
  {
    'target_name': 'exe',
    'type': 'executable',
    'dependencies': [ 'lib', ],
    'sources': 'my_other_file.cc',
    'xcode_settings': {
      'ARCHS': [ 'x86_64', ],
    },
  },
}

In this case, the executable is built for 64 bit, but the library it links in is
only 32 bit. What does xcodebuild do in this case? I believe this will error out
in make /ninja with your patch, and I think xcodebuild handles this correctly
somehow (not sure though).

+    else:
+      # TODO: Supporting fat binaries will be annoying.
+      self._WarnUnimplemented('ARCHS')
+      cflags.append('-arch i386')
 
     cflags += self._Settings().get('OTHER_CFLAGS', [])
     cflags += self._Settings().get('WARNING_CFLAGS', [])
 
     config = self.spec['configurations'][self.configname]
     framework_dirs = config.get('mac_framework_dirs', [])
     for directory in framework_dirs:
       cflags.append('-F ' + directory.replace('$(SDKROOT)', sdk_root))
 
     self.configname = None
@@ skipping 81 matching lines @@
       ldflags.append('-isysroot ' + self._SdkPath())
 
     for library_path in self._Settings().get('LIBRARY_SEARCH_PATHS', []):
       ldflags.append('-L' + gyp_to_build_path(library_path))
 
     if 'ORDER_FILE' in self._Settings():
       ldflags.append('-Wl,-order_file ' +
                      '-Wl,' + gyp_to_build_path(
                                   self._Settings()['ORDER_FILE']))
 
-    # TODO: Do not hardcode arch. Supporting fat binaries will be annoying.
-    ldflags.append('-arch i386')
+    archs = self._Settings().get('ARCHS', ['i386'])
+    if len(archs) == 0:
+      pass
+    elif len(archs) == 1:
+      ldflags.append('-arch ' + archs[0])
+    else:
+      # TODO: Supporting fat binaries will be annoying.
+      self._WarnUnimplemented('ARCHS')
+      ldflags.append('-arch i386')
 
     # Xcode adds the product directory by default.
     ldflags.append('-L' + product_dir)
 
     install_name = self.GetPerTargetSetting('LD_DYLIB_INSTALL_NAME')
     install_base = self.GetPerTargetSetting('DYLIB_INSTALL_NAME_BASE')
     default_install_name = \
           '$(DYLIB_INSTALL_NAME_BASE:standardizepath)/$(EXECUTABLE_PATH)'
     if not install_name and install_base:
       install_name = default_install_name
@@ skipping 539 matching lines @@
     # absolutified. Else, it's in the PATH (e.g. install_name_tool, ln).
     if os.path.sep in shell_list[0]:
       shell_list[0] = gyp_path_to_build_path(shell_list[0])
 
       # "script.sh" -> "./script.sh"
       if not os.path.sep in shell_list[0]:
         shell_list[0] = os.path.join('.', shell_list[0])
     postbuilds.append(gyp.common.EncodePOSIXShellList(shell_list))
 
   return postbuilds