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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<div class='path'>path: <a href='/guix/log/?id=4a828263791ebb8ed8f8104e015a8f467008fc76'>root</a>/<a href='/guix/log/gnu?id=4a828263791ebb8ed8f8104e015a8f467008fc76'>gnu</a>/<a href='/guix/log/gnu/system?id=4a828263791ebb8ed8f8104e015a8f467008fc76'>system</a>/<a href='/guix/log/gnu/system/linux-container.scm?id=4a828263791ebb8ed8f8104e015a8f467008fc76'>linux-container.scm</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/gnu/system/linux-container.scm?id=4a828263791ebb8ed8f8104e015a8f467008fc76&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2022-03-19 18:26:00 +0100'>2022-03-19</span></td><td><a href='/guix/commit/gnu/system/linux-container.scm?id=cff9fee82a06f58b10a5b3a7743295c53f7988b8'>linux-container: Add #:guest-uid and #:guest-gid to 'eval/container'.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/system/linux-container.scm (eval/container): Add #:guest-uid
and #:guest-gid and honor them.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2022-03-19 18:26:00 +0100'>2022-03-19</span></td><td><a href='/guix/commit/gnu/system/linux-container.scm?id=c77544b387882450599b5f7e2712abdadaa074e9'>linux-container: 'eval/container' honors #:namespaces.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/system/linux-container.scm (eval/container): Pass #:namespaces to
'call-with-container'.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2021-01-13 22:24:18 +0100'>2021-01-13</span></td><td><a href='/guix/commit/gnu/system/linux-container.scm?id=0d22fc8d36e4efba9748c94cab7cedbbe2bbb5bf'>services: shepherd: 'shepherd-service-type' requires documentation.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/services/shepherd.scm (shepherd-service-type): Require a
'description' form.
* gnu/services/base.scm (root-file-system-service-type)
(rngd-service-type, host-name-service-type):
(virtual-terminal-service-type, console-keymap-service-type)
(syslog-service-type, swap-service-type)
(kmscon-service-type): Add description.
* gnu/services/networking.scm (dhcp-client-service-type): Likewise.
* gnu/system/install.scm (cow-store-service-type): Likewise.
* gnu/system/linux-container.scm (dummy-networking-service-type):
Likewise.
* gnu/system/mapped-devices.scm (device-mapping-service-type):
Likewise.
* tests/guix-system.sh: Likewise.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2020-10-01 09:27:33 +0200'>2020-10-01</span></td><td><a href='/guix/commit/gnu/system/linux-container.scm?id=5627bfe45ce46f498979b4ad2deab1fdfed22b6c'>Instantiate nscd in each system container.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/system/linux-container.scm (%nscd-container-caches): New variable.
(containerized-operating-system): Instantiate nscd-service with smaller caches
and add it to the generated operating-system, replacing any nscd-service
specified by the caller.
* gnu/system/file-systems.scm: (%network-file-mappings): Remove "/var/run/nscd".

Signed-off-by: Mathieu Othacehe &lt;othacehe@gnu.org&gt;
</span></span></td><td>Jason Conroy</td></tr>
<tr><td><span title='2020-04-26 22:49:49 +0200'>2020-04-26</span></td><td><a href='/guix/commit/gnu/system/linux-container.scm?id=0e5c2d5e145118ec47329d6b3a534344d2e89cd3'>services: system: Initial entries are non-monadic.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/system.scm (operating-system-directory-base-entries): Return a
regular, non-monadic value.
* gnu/services.scm (system-derivation): Adjust accordingly.
* gnu/system/linux-container.scm (container-essential-services): Likewise.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2020-01-06 12:20:21 +0200'>2020-01-06</span></td><td><a href='/guix/commit/gnu/system/linux-container.scm?id=c27710859c3cb59c439571ddc56cf71c36a1c33c'>system: linux-container: Recommend guix container.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/system/linux-container.scm (container-script)[script]: Recommend
using 'guix container' to get a shell inside the running container.
</span></span></td><td>Efraim Flashner</td></tr>