is overriden with the CC environment variable, use the new compiler as
the default for linking if LDSHARED is not also overriden. This restores
Distutils behavior introduced in 2.7.3 and inadvertently dropped in 2.7.4.
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.
has left two versions of customize_compiler, the original in
distutils.sysconfig and another copy in distutils.ccompiler, with some
parts of distutils calling one and others using the other.
Complete the revert back to only having one in distutils.sysconfig as
is the case in 3.x.
Distutils-based packages with C extension modules may fail because
Apple has removed gcc-4.2, the version used to build python.org
64-bit/32-bit Pythons. If the user does not explicitly override
the default C compiler by setting the CC environment variable,
Distutils will now attempt to compile extension modules with clang
if gcc-4.2 is required but not found. Also as a convenience, if
the user does explicitly set CC, substitute its value as the default
compiler in the Distutils LDSHARED configuration variable for OS X.
(Note, the python.org 32-bit-only Pythons use gcc-4.0 and the 10.4u
SDK, neither of which are available in Xcode 4. This change does not
attempt to override settings to support their use with Xcode 4.)
set the MACOSX_DEPLOYMENT_TARGET env variable for the interpreter process
on OS X. This could cause failures in non-distutils subprocesses and was
unreliable since tests or user programs could modify the interpreter
environment after distutils set it. Instead, have distutils set the
the deployment target only in the environment of each build subprocess.
Continue to use the previous algorithm for deriving the deployment target
value:
if MACOSX_DEPLOYMENT_TARGET is not set in the interpreter's env:
use the interpreter build configure MACOSX_DEPLOYMENT_TARGET
elif the MACOSX_DEPLOYMENT_TARGET env value >= configure value:
use the env MACOSX_DEPLOYMENT_TARGET
else: # env value less than interpreter build configure value
raise exception
This allows building extensions that can only run on newer versions of
the OS than the version python was built for, for example with a python
built for 10.3 or later and an extension that needs to be built for 10.5.
Without this patch python will fail to start properly when the environment
variable MACOSX_DEPLOYMENT_TARGET is set on MacOSX and has a value that is
not compatible with the value during Python's build. This is caused by code
in sysconfig that was only meant to be used in disutils.
This was overlooked in r80804. This change is not really a bug fix,
but the release manager agreed to it. There is no NEWS entry, like
in the original commit.
to "sys.platform == 'mac'" and that is
dead code because it refers to a platform
that is no longer supported (and hasn't been
supported for several releases).
Fixes issue #7908 for the trunk.
on OSX. Without this patch it wasn't possible after all
to compile extensions on OSX 10.6 with the binary
installer unless the user had installed the (non-default)
10.4u SDK.
ignores the '-isysroot' option on OSX when the
corresponding SDK is not installed.
This ensures that the user can compile extensions
on OSX 10.6 using the Python.org installer and a
default installation of Xcode.
