diff --git a/Makefile.OpenArena b/Makefile.OpenArena
index 5ad6b15f..c8608de4 100644
--- a/Makefile.OpenArena
+++ b/Makefile.OpenArena
@@ -49,6 +49,8 @@ GLSL_TEXTURES		=1		# for shaders on models, leifxdither, etc
 GLSL_BACKEND		=1		# for the entire backend.
 
 
+#Possible values "gnu90", "gnu99" and "gnu11". Note that the engine uses gnu-extensions. gnu90 is broken in the commit where this message is added.
+CFLAGS+="-std=gnu11"
 
 
 # You can change these although you probably don't need to