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 +526,10 @@ 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.
+        lib_dirs += os.getenv('LIBRARY_PATH', '').split(os.pathsep)
+        inc_dirs += os.getenv('C_INCLUDE_PATH', '').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='2021-12-13 17:48:25 +0100'>2021-12-13</span></td><td><a href='/guix/commit/gnu/packages/libftdi.scm?id=8394619baceb118df92e355377fd543bb1aa501a'>gnu: Simplify package inputs.</a><span class='msg-avail'>...<span class='msg-tooltip'>This commit was obtained by running:

  ./pre-inst-env guix style

without any additional argument.
</span></span></td><td>Ludovic Courtès</td></tr>