python: add patch to fix logic to get gcc paths

The Python setup.py has a function called add_gcc_paths(), which
executes gcc -E -v to get the list of header paths searched by
gcc. However, the logic of setup.py is only valid with the normal
english output of gcc: it doesn't work if a non-english locale is
set. This causes setup.py to not find certain headers (such as zlib.h)
and therefore disabling the build of such extensions.

Reported-by: Bruno Coudoin <bruno.coudoin@gcompris.net>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/python/018-fix-add-gcc-paths-logic.patch

@@ -0,0 +1,27 @@
+Override system locale and set to default when adding gcc paths
+
+Forces the use of the default locale in the function
+add_gcc_paths, which is called when cross compiling to add the
+include and library paths. This is necessary because otherwise
+the gcc output is localized and the output parsing fails, which
+results in no paths added and detect_modules not able to find
+any system library (eg. libz, libssl, etc.)
+
+[Thomas: patch taken from https://bugs.python.org/issue23767.]
+
+Signed-off-by: Samuel Cabrero <samuelcabrero@gmail.com>
+Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
+
+Index: b/setup.py
+===================================================================
+--- a/setup.py
++++ b/setup.py
+@@ -414,7 +414,7 @@
+         tmpfile = os.path.join(self.build_temp, 'gccpaths')
+         if not os.path.exists(self.build_temp):
+             os.makedirs(self.build_temp)
+-        ret = os.system('%s -E -v - </dev/null 2>%s 1>/dev/null' % (gcc, tmpfile))
++        ret = os.system('LC_ALL=C %s -E -v - </dev/null 2>%s 1>/dev/null' % (gcc, tmpfile))
+         is_gcc = False
+         in_incdirs = False
+         inc_dirs = []