diff --git a/doc/README.developer b/doc/README.developer
index cbca41f014..300be484f4 100644
--- a/doc/README.developer
+++ b/doc/README.developer
@@ -241,6 +241,23 @@ to implement it.  Use something like
 
 instead.
 
+Don't use "variadic macros", such as
+
+	#define DBG(format, args...)	fprintf(stderr, format, ## args)
+
+as not all C compilers support them.  Use macros that take a fixed
+number of arguments, such as
+
+	#define DBG0(format)		fprintf(stderr, format)
+	#define DBG1(format, arg1)	fprintf(stderr, format, arg1)
+	#define DBG2(format, arg1, arg2) fprintf(stderr, format, arg1, arg2)
+
+		...
+
+or something such as
+
+	#define DBG(args)		printf args
+
 snprintf() -> g_snprintf()
 snprintf() is not available on all platforms, so it's a good idea to use the 
 g_snprintf() function declared by <glib.h> instead.