Second patch to bring cross-compilation support to python build-system.

Allow the libraries detection routine to look for headers and libs in
other directories than /usr/include or /usr/lib through the env variables
PYTHON_MODULES_INCLUDE and PYTHON_MODULES_LIB.

We can then use it to look for libraries in the buildroot staging directory.


Patch ported to python2.7 by Maxime Ripard <ripard@archos.com>

diff -rduNp Python-2.7.orig/setup.py Python-2.7/setup.py
--- Python-2.7.orig/setup.py	2010-09-21 17:15:31.000000000 +0200
+++ Python-2.7/setup.py	2010-09-21 17:20:46.000000000 +0200
@@ -346,6 +346,18 @@ class PyBuildExt(build_ext):
         return sys.platform
 
     def detect_modules(self):
+        try:
+            modules_include_dirs = os.environ["PYTHON_MODULES_INCLUDE"].split()
+        except KeyError:
+            modules_include_dirs = ['/usr/include']
+        try:
+            modules_lib_dirs = os.environ["PYTHON_MODULES_LIB"].split()
+        except KeyError:
+            modules_include_dirs = ['/usr/lib']
+        for dir in modules_include_dirs:
+            add_dir_to_list(self.compiler.include_dirs, dir)
+        for dir in modules_lib_dirs:
+            add_dir_to_list(self.compiler.library_dirs, dir)
         # Add paths specified in the environment variables LDFLAGS and
         # CPPFLAGS for header and library files.
         # We must get the values from the Makefile and not the environment
@@ -388,11 +400,8 @@ class PyBuildExt(build_ext):
         # lib_dirs and inc_dirs are used to search for files;
         # if a file is found in one of those directories, it can
         # be assumed that no additional -I,-L directives are needed.
-        lib_dirs = self.compiler.library_dirs + [
-            '/lib64', '/usr/lib64',
-            '/lib', '/usr/lib',
-            ]
-        inc_dirs = self.compiler.include_dirs + ['/usr/include']
+        lib_dirs = self.compiler.library_dirs
+        inc_dirs = self.compiler.include_dirs
         exts = []
         missing = []