when imported, instead doing it at build time.  This makes importing
  sysconfig faster and reduces Python startup time by 20%.

as reported by Serhiy Storchaka and Matthew Barnett.

The customize_compiler function moved many times during the 2.7 series;
in 2.7.3, setup scripts importing this function from ccompiler were
broken.  This commit restores compatibility without reintroducing the
issue that #13994 originally fixed (duplication of the function).

A unit test makes little sense here, as distutils tests never do imports
in functions, and the fix is very simple.

  the package.

    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.

  --without-doc-strings option.

Patch by Serhiy Storchaka.

Original patch by Julien Courteau and Pierre Paul Lefebvre.

There was a window between the write and the chmod where the user’s
password would be exposed, depending on default permissions.  Philip
Jenvey’s patch fixes it.

These files are created by some NFS clients a file is edited and removed
concurrently (see added link in doc for more info).  If such a file is
removed between distutils calls listdir and copy, it will get confused.
Other special files are ignored in sdist (namely VCS directories), but
this has to be filtered out earlier.

Patch by Ralf Schmitt.

- Actually check the contents of the file created by bdist_dumb.
- Don’t use “RECORD” as filename for non-PEP 376 record file
- Don’t start method name with “_test”, it looks like a disabled test
  method instead of an helper method
- Fix some idioms (assertIn, addCleanup)

Bug reported by Hartmut Goebel and patch contributed by Carl Robben.
Untested backport of the fix committed and tested for 3.2.

These regex changes fix a number of issues for distutils on Windows:
- #6884: impossible to include a file starting with 'build'
- #9691 and #14004: sdist includes too many files
- #13193: test_filelist failures

This commit replaces the incorrect changes done in 557a973709de,
c566a3447ba1 and 3925081a7ca0 to fix #13193; we were too eager to fix
the test failures and I did not study the code enough before
greenlighting patches.  This time we have unit tests from the problems
reported by users to be sure we have the right fix.

Thanks to Nadeem Vawda for his help.

These regex changes fix a number of issues for distutils on Windows:
- #6884: impossible to include a file starting with 'build'
- #9691 and #14004: sdist includes too many files
- #13193: test_filelist failures

This commit replaces the incorrect changes done in 557a973709de,
c566a3447ba1 and 3925081a7ca0 to fix #13193; we were too eager to fix
the test failures and I did not study the code enough before
greenlighting patches.  This time we have unit tests from the problems
reported by users to be sure we have the right fix.

Thanks to Nadeem Vawda for his help.

The code used to call os.path.join to build a regex but without escaping
the backslash, which lead to test failures on Windows.  Antoine Pitrou
fixed it in 557a973709de by enhancing the code to accept both / and \,
with proper escaping, but in my opinion this goes against the distutils
feature freeze, hence this change.

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.)