Issue #13590: OS X Xcode 4 - improve support for universal extension modules
In particular, fix extension module build failures when trying to use
32-bit-only installer Pythons on systems with Xcode 4 (currently
OS X 10.8, 10.7, and optionally 10.6).
* Backport 3.3.0 fixes to 2.7 branch (for release in 2.7.4)
* Since Xcode 4 removes ppc support, extension module builds now
check for ppc compiler support and by default remove ppc and
ppc64 archs when they are not available.
* Extension module builds now revert to using system installed
headers and libs (/usr and /System/Library) if the SDK used
to build the interpreter is not installed or has moved.
* Try to avoid building extension modules with deprecated
and problematic Apple llvm-gcc compiler. If original compiler
is not available, use clang instead by default.
diff --git a/Lib/distutils/sysconfig.py b/Lib/distutils/sysconfig.py
index 4b193b2..daa4dc7 100644
--- a/Lib/distutils/sysconfig.py
+++ b/Lib/distutils/sysconfig.py
@@ -141,7 +141,7 @@
"I don't know where Python installs its library "
"on platform '%s'" % os.name)
-_USE_CLANG = None
+
def customize_compiler(compiler):
"""Do any platform-specific customization of a CCompiler instance.
@@ -150,6 +150,21 @@
varies across Unices and is stored in Python's Makefile.
"""
if compiler.compiler_type == "unix":
+ if sys.platform == "darwin":
+ # Perform first-time customization of compiler-related
+ # config vars on OS X now that we know we need a compiler.
+ # This is primarily to support Pythons from binary
+ # installers. The kind and paths to build tools on
+ # the user system may vary significantly from the system
+ # that Python itself was built on. Also the user OS
+ # version and build tools may not support the same set
+ # of CPU architectures for universal builds.
+ global _config_vars
+ if not _config_vars.get('CUSTOMIZED_OSX_COMPILER', ''):
+ import _osx_support
+ _osx_support.customize_compiler(_config_vars)
+ _config_vars['CUSTOMIZED_OSX_COMPILER'] = 'True'
+
(cc, cxx, opt, cflags, ccshared, ldshared, so_ext, ar, ar_flags) = \
get_config_vars('CC', 'CXX', 'OPT', 'CFLAGS',
'CCSHARED', 'LDSHARED', 'SO', 'AR',
@@ -157,36 +172,7 @@
newcc = None
if 'CC' in os.environ:
- newcc = os.environ['CC']
- elif sys.platform == 'darwin' and cc == 'gcc-4.2':
- # Issue #13590:
- # Since Apple removed gcc-4.2 in Xcode 4.2, we can no
- # longer assume it is available for extension module builds.
- # If Python was built with gcc-4.2, check first to see if
- # it is available on this system; if not, try to use clang
- # instead unless the caller explicitly set CC.
- global _USE_CLANG
- if _USE_CLANG is None:
- from distutils import log
- from subprocess import Popen, PIPE
- p = Popen("! type gcc-4.2 && type clang && exit 2",
- shell=True, stdout=PIPE, stderr=PIPE)
- p.wait()
- if p.returncode == 2:
- _USE_CLANG = True
- log.warn("gcc-4.2 not found, using clang instead")
- else:
- _USE_CLANG = False
- if _USE_CLANG:
- newcc = 'clang'
- if newcc:
- # On OS X, if CC is overridden, use that as the default
- # command for LDSHARED as well
- if (sys.platform == 'darwin'
- and 'LDSHARED' not in os.environ
- and ldshared.startswith(cc)):
- ldshared = newcc + ldshared[len(cc):]
- cc = newcc
+ cc = os.environ['CC']
if 'CXX' in os.environ:
cxx = os.environ['CXX']
if 'LDSHARED' in os.environ:
@@ -518,66 +504,11 @@
_config_vars['prefix'] = PREFIX
_config_vars['exec_prefix'] = EXEC_PREFIX
+ # OS X platforms require special customization to handle
+ # multi-architecture, multi-os-version installers
if sys.platform == 'darwin':
- kernel_version = os.uname()[2] # Kernel version (8.4.3)
- major_version = int(kernel_version.split('.')[0])
-
- if major_version < 8:
- # On Mac OS X before 10.4, check if -arch and -isysroot
- # are in CFLAGS or LDFLAGS and remove them if they are.
- # This is needed when building extensions on a 10.3 system
- # using a universal build of python.
- for key in ('LDFLAGS', 'BASECFLAGS', 'LDSHARED',
- # a number of derived variables. These need to be
- # patched up as well.
- 'CFLAGS', 'PY_CFLAGS', 'BLDSHARED'):
- flags = _config_vars[key]
- flags = re.sub('-arch\s+\w+\s', ' ', flags)
- flags = re.sub('-isysroot [^ \t]*', ' ', flags)
- _config_vars[key] = flags
-
- else:
-
- # Allow the user to override the architecture flags using
- # an environment variable.
- # NOTE: This name was introduced by Apple in OSX 10.5 and
- # is used by several scripting languages distributed with
- # that OS release.
-
- if 'ARCHFLAGS' in os.environ:
- arch = os.environ['ARCHFLAGS']
- for key in ('LDFLAGS', 'BASECFLAGS', 'LDSHARED',
- # a number of derived variables. These need to be
- # patched up as well.
- 'CFLAGS', 'PY_CFLAGS', 'BLDSHARED'):
-
- flags = _config_vars[key]
- flags = re.sub('-arch\s+\w+\s', ' ', flags)
- flags = flags + ' ' + arch
- _config_vars[key] = flags
-
- # If we're on OSX 10.5 or later and the user tries to
- # compiles an extension using an SDK that is not present
- # on the current machine it is better to not use an SDK
- # than to fail.
- #
- # The major usecase for this is users using a Python.org
- # binary installer on OSX 10.6: that installer uses
- # the 10.4u SDK, but that SDK is not installed by default
- # when you install Xcode.
- #
- m = re.search('-isysroot\s+(\S+)', _config_vars['CFLAGS'])
- if m is not None:
- sdk = m.group(1)
- if not os.path.exists(sdk):
- for key in ('LDFLAGS', 'BASECFLAGS', 'LDSHARED',
- # a number of derived variables. These need to be
- # patched up as well.
- 'CFLAGS', 'PY_CFLAGS', 'BLDSHARED'):
-
- flags = _config_vars[key]
- flags = re.sub('-isysroot\s+\S+(\s|$)', ' ', flags)
- _config_vars[key] = flags
+ import _osx_support
+ _osx_support.customize_config_vars(_config_vars)
if args:
vals = []