diff --git a/gcc/system.h b/gcc/system.h
index 42bc509f2..9a2d9852c 100644
--- a/gcc/system.h
+++ b/gcc/system.h
@@ -69,6 +69,9 @@ along with GCC; see the file COPYING3.  If not see
    fputs_unlocked, fwrite_unlocked, and fprintf_unlocked are
    extensions and need to be prototyped by hand (since we do not
    define _GNU_SOURCE).  */
+#if defined(__MACH__)
+#undef HAVE_DECL_PUTC_UNLOCKED
+#endif
 
 #if defined HAVE_DECL_PUTC_UNLOCKED && HAVE_DECL_PUTC_UNLOCKED
 
@@ -463,8 +466,12 @@ extern char *stpcpy (char *, const char *);
 #endif
 
 #ifdef HAVE_MALLOC_H
+#if defined(__MACH__)
+#include <stdlib.h>
+#else
 #include <malloc.h>
 #endif
+#endif
 
 #ifdef __cplusplus
 extern "C" {