diff --git a/H/Yap.h b/H/Yap.h
index 74fa8d810..c13bed032 100644
--- a/H/Yap.h
+++ b/H/Yap.h
@@ -691,7 +691,13 @@ typedef enum
 	if you place things in the lower addresses (power to the libc people).
 */
 
-#if (defined(_AIX) || (defined(__APPLE__) && !defined(__LP64__)) || defined(_WIN32) || defined(sparc) || defined(__sparc) || defined(mips) || defined(__FreeBSD__) || defined(_POWER) || defined(__POWERPC__) || defined(__linux__) || defined(IN_SECOND_QUADRANT) || defined(__CYGWIN__)) || defined(__NetBSD__) || defined(__DragonFly__)
+#if defined(__APPLE__)
+/* mmap on __APPLE__ is not the greatest idea. It overwrites memory allocated by malloc */
+#undef USE_DL_MALLOC
+#ifndef USE_SYSTEM_MALLOC
+#define USE_SYSTEM_MALLOC 1
+#endif
+#elif (defined(_AIX) || (defined(__APPLE__) && !defined(__LP64__)) || defined(_WIN32) || defined(sparc) || defined(__sparc) || defined(mips) || defined(__FreeBSD__) || defined(_POWER) || defined(__POWERPC__) || defined(__linux__) || defined(IN_SECOND_QUADRANT) || defined(__CYGWIN__)) || defined(__NetBSD__) || defined(__DragonFly__)
 #define USE_LOW32_TAGS 1
 #endif