diff --git a/BaseTools/Source/C/GenFv/GNUmakefile b/BaseTools/Source/C/GenFv/GNUmakefile
--- a/BaseTools/Source/C/GenFv/GNUmakefile
+++ b/BaseTools/Source/C/GenFv/GNUmakefile
@@ -21,8 +21,8 @@
 ifndef CROSS_LIB_UUID
   LIBS += -luuid
 else
   LIBS += -L$(CROSS_LIB_UUID)
-  BUILD_CFLAGS += -D__CROSS_LIB_UUID__ -I $(CROSS_LIB_UUID_INC)
+  CFLAGS += -D__CROSS_LIB_UUID__ -I $(CROSS_LIB_UUID_INC)
 endif
 endif