--- gcc/config/i386/sysv3.h	2018/04/24 18:10:27	1.1.1.1
+++ gcc/config/i386/sysv3.h	2018/04/24 18:16:40	1.1.1.2
@@ -41,7 +41,7 @@ the Free Software Foundation, 675 Mass A
 
 /* Specify predefined symbols in preprocessor.  */
 
-#define CPP_PREDEFINES "-Dunix -Di386"
+#define CPP_PREDEFINES "-Dunix -Di386 -Asystem(unix) -Asystem(svr3) -Acpu(i386) -Amachine(i386)"
 
 #define CPP_SPEC "%{posix:-D_POSIX_SOURCE}"