From 5f3b60573e55d379b943a45159180196d27b2e90 Mon Sep 17 00:00:00 2001
From: Ian Abbott <abbotti@mev.co.uk>
Date: Wed, 21 Aug 2013 11:06:24 +0100
Subject: [PATCH] m4/am-check-python-headers.m4: Try python-config --includes

Some systems (e.g. Arch Linux) put the Python C headers in a strange
place, so try and run `$PYTHON-config --includes` first to find the -I
options to pass to the C compiler.  Fall back to the old method if it
fails.

Thanks to Darrell Enns for reporting the problem and suggesting a
solution.  I changed it a bit.
---
 m4/am-check-python-headers.m4 | 26 +++++++++++++++++---------
 1 file changed, 17 insertions(+), 9 deletions(-)

diff --git a/m4/am-check-python-headers.m4 b/m4/am-check-python-headers.m4
index 4a97740..b9f1222 100644
--- a/m4/am-check-python-headers.m4
+++ b/m4/am-check-python-headers.m4
@@ -3,22 +3,30 @@ dnl  AM_CHECK_PYTHON_HEADERS([ACTION-IF-POSSIBLE], [ACTION-IF-NOT-POSSIBLE])
 dnl function also defines PYTHON_INCLUDES
 AC_DEFUN([AM_CHECK_PYTHON_HEADERS],
 [AC_REQUIRE([AM_PATH_PYTHON])
-AC_MSG_CHECKING(for headers required to compile python extensions)
 dnl deduce PYTHON_INCLUDES
-py_prefix=`$PYTHON -c "import sys; print(sys.prefix)"`
-py_exec_prefix=`$PYTHON -c "import sys; print(sys.exec_prefix)"`
-PYTHON_INCLUDES="-I${py_prefix}/include/python${PYTHON_VERSION}"
-if test "$py_prefix" != "$py_exec_prefix"; then
-  PYTHON_INCLUDES="$PYTHON_INCLUDES -I${py_exec_prefix}/include/python${PYTHON_VERSION}"
+AC_MSG_CHECKING([for python headers using $PYTHON-config --includes])
+PYTHON_INCLUDES=`$PYTHON-config --includes`
+if test $? = 0; then
+  AC_MSG_RESULT([$PYTHON_INCLUDES])
+else
+  AC_MSG_RESULT([failed, will try another way])
+  py_prefix=`$PYTHON -c "import sys; print(sys.prefix)"`
+  py_exec_prefix=`$PYTHON -c "import sys; print(sys.exec_prefix)"`
+  PYTHON_INCLUDES="-I${py_prefix}/include/python${PYTHON_VERSION}"
+  if test "$py_prefix" != "$py_exec_prefix"; then
+    PYTHON_INCLUDES="$PYTHON_INCLUDES -I${py_exec_prefix}/include/python${PYTHON_VERSION}"
+  fi
+  AC_MSG_NOTICE([setting python headers to $PYTHON_INCLUDES])
 fi
-AC_SUBST(PYTHON_INCLUDES)
 dnl check if the headers exist:
+AC_MSG_CHECKING([whether python headers are sufficient])
+AC_SUBST(PYTHON_INCLUDES)
 save_CPPFLAGS="$CPPFLAGS"
 CPPFLAGS="$CPPFLAGS $PYTHON_INCLUDES"
 AC_TRY_CPP([#include <Python.h>],dnl
-[AC_MSG_RESULT(found)
+[AC_MSG_RESULT(yes)
 $1],dnl
-[AC_MSG_RESULT(not found)
+[AC_MSG_RESULT(no)
 $2])
 CPPFLAGS="$save_CPPFLAGS"
 ])