diff --git a/libswscale/swscale.c b/libswscale/swscale.c
index 54e391cce6ae2c96e7fcb6146990df099c61ba0b..c4b14c9d837623780d7db561bd3adea887102501 100644
--- a/libswscale/swscale.c
+++ b/libswscale/swscale.c
@@ -54,6 +54,7 @@ untested special converters
   BGR24 -> YV12
 */
 
+#define _SVID_SOURCE //needed for MAP_ANONYMOUS
 #include <inttypes.h>
 #include <string.h>
 #include <math.h>