Build as C99

diff --git a/x5/Makefile b/x5/Makefile
index 59d115b..585ca12 100644 (file)
--- a/x5/Makefile
+++ b/x5/Makefile
@@ -1,5 +1,6 @@
-CFLAGS := -Wall -Wextra
-LDLIBS := -lX11
+CPPFLAGS := -D_POSIX_C_SOURCE=200809L
+CFLAGS   := -std=c99 -Wall -Wextra
+LDLIBS   := -lX11
 
 .PHONY: build clean rebuild