Index: mesa/configure.ac
===================================================================
--- mesa.orig/configure.ac	2014-06-03 14:51:52.482665407 +0400
+++ mesa/configure.ac	2014-06-03 19:12:45.434864010 +0400
@@ -45,6 +45,7 @@
 AC_PROG_CXX
 AM_PROG_CC_C_O
 AM_PROG_AS
+AC_USE_SYSTEM_EXTENSIONS
 AC_CHECK_PROGS([MAKE], [gmake make])
 AC_CHECK_PROGS([PYTHON2], [python2 python])
 AX_PYTHON_MODULE([libxml2], [needed])