diff -r 8d4b2c6a0a7f Include/pyport.h
--- a/Include/pyport.h	Wed Dec 07 20:41:42 2016 +0900
+++ b/Include/pyport.h	Wed Dec 07 19:13:18 2016 +0100
@@ -37,9 +37,11 @@
  * integral synonyms.  Only define the ones we actually need.
  */
 
-// long long is required now. Define HAVE_LONG_LONG unconditionally for
-// compatibility.
+// long long is required now. Define HAVE_LONG_LONG, if it is not defined,
+// for compatibility.
+#ifndef HAVE_LONG_LONG
 #define HAVE_LONG_LONG
+#endif
 #ifndef PY_LONG_LONG
 #define PY_LONG_LONG long long
 /* If LLONG_MAX is defined in limits.h, use that. */