Make sure the build system honors C_INCLUDE_PATH and LIBRARY_PATH when
looking for headers and libraries.

--- Python-2.7.10/setup.py	2015-10-07 18:33:18.125153186 +0200
+++ Python-2.7.10/setup.py	2015-10-07 18:33:47.497347552 +0200
@@ -526,6 +526,14 @@ class PyBuildExt(build_ext):
             inc_dirs += ['/system/include', '/atheos/autolnk/include']
             inc_dirs += os.getenv('C_INCLUDE_PATH', '').split(os.pathsep)
 
+        # Always honor these variables.
+        if not cross_compiling:
+            lib_dirs += os.getenv('LIBRARY_PATH', '').split(os.pathsep)
+            inc_dirs += os.getenv('C_INCLUDE_PATH', '').split(os.pathsep)
+        else:
+            lib_dirs = os.getenv('CROSS_LIBRARY_PATH', '').split(os.pathsep)
+            inc_dirs = os.getenv('CROSS_CPATH', '').split(os.pathsep)
+
         # OSF/1 and Unixware have some stuff in /usr/ccs/lib (like -ldb)
         if host_platform in ['osf1', 'unixware7', 'openunix8']:
             lib_dirs += ['/usr/ccs/lib']
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<tr><td><span title='2021-07-29 13:09:48 -0400'>2021-07-29</span></td><td><a href='/guix/commit/gnu/system/setuid.scm?id=45235e67e4aeac96ad8d60265bef054990aeb425'>system: Add (gnu system setuid).</a><span class='msg-avail'>...<span class='msg-tooltip'>I flubbed and somehow when including the patch series, this got dropped.
Oops... should fix things again.

* gnu/system/setuid.scm: New file.
</span></span></td><td>Christopher Lemmer Webber</td></tr>