--- gcc/config/xm-i386.h	2018/04/24 16:53:27	1.1.1.1
+++ gcc/config/xm-i386.h	2018/04/24 16:57:08	1.1.1.3
@@ -36,3 +36,7 @@ the Free Software Foundation, 675 Mass A
    tm.h is a symbolic link to the actual target specific file.   */
 
 #include "tm.h"
+
+#ifdef __GNUC__
+#define alloca __builtin_alloca
+#endif