diff --git a/solenv/inc/unxmacxp.mk b/solenv/inc/unxmacxp.mk
index 56d0876fdd2d..f8adb5f7aa53 100644
--- a/solenv/inc/unxmacxp.mk
+++ b/solenv/inc/unxmacxp.mk
@@ -17,7 +17,7 @@ CC=cc
 cc=cc
 objc=cc
 CFLAGS=-c $(INCLUDE)
-CFLAGSCC=-pipe
+CFLAGSCC=-pipe -traditional-cpp
 
 OBJCFLAGS=-no-precomp