diff --git a/libswscale/utils.c b/libswscale/utils.c
index b75510d206..dcab707de6 100644
--- a/libswscale/utils.c
+++ b/libswscale/utils.c
@@ -1574,7 +1574,11 @@ av_cold int sws_init_context(SwsContext *c, SwsFilter *srcFilter,
         }
     }
 
-#define USE_MMAP (HAVE_MMAP && HAVE_MPROTECT && defined MAP_ANONYMOUS)
+#if HAVE_MMAP && HAVE_MPROTECT && defined(MAP_ANONYMOUS)
+#define USE_MMAP 1
+#else
+#define USE_MMAP 0
+#endif
 
     /* precalculate horizontal scaler filter coefficients */
     {