Index: setup.py
===================================================================
--- setup.py	(revision 74942)
+++ setup.py	(working copy)
@@ -1768,7 +1768,12 @@
             # in /usr/include/ffi
             inc_dirs.append('/usr/include/ffi')
 
-        ffi_inc = find_file('ffi.h', [], inc_dirs)
+        try:
+            ffi_inc = [flag[2:] for flag in os.popen('pkg-config libffi --cflags').read().split() if flag[:2] == '-I']
+        except OSError:
+            ffi_inc = None
+        if not ffi_inc:
+            ffi_inc = find_file('ffi.h', [], inc_dirs)
         if ffi_inc is not None:
             ffi_h = ffi_inc[0] + '/ffi.h'
             fp = open(ffi_h)