updated for version 7.3.368
Problem: Gcc complains about redefining _FORTIFY_SOURCE.
Solution: Undefine it before redefining it.
diff --git a/src/Makefile b/src/Makefile
index 5b32482..869298c 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -561,8 +561,8 @@
#CFLAGS = -g -O2 '-DSTARTUPTIME="vimstartup"' -fno-strength-reduce -Wall -Wmissing-prototypes
# Use this with GCC to check for mistakes, unused arguments, etc.
-#CFLAGS = -g -Wall -Wextra -Wmissing-prototypes -Wunreachable-code -D_FORTIFY_SOURCE=1
-#CFLAGS = -g -O2 -Wall -Wextra -Wmissing-prototypes -D_FORTIFY_SOURCE=1 -DU_DEBUG
+#CFLAGS = -g -Wall -Wextra -Wmissing-prototypes -Wunreachable-code -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=1
+#CFLAGS = -g -O2 -Wall -Wextra -Wmissing-prototypes -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=1 -DU_DEBUG
#PYTHON_CFLAGS_EXTRA = -Wno-missing-field-initializers
#MZSCHEME_CFLAGS_EXTRA = -Wno-unreachable-code -Wno-unused-parameter