diff --git a/mach/proto/cg/gencode.c b/mach/proto/cg/gencode.c
index ea1ccbe5c..6fc93d497 100644
--- a/mach/proto/cg/gencode.c
+++ b/mach/proto/cg/gencode.c
@@ -35,7 +35,7 @@ FILE *codefile;
 out_init(filename) char *filename; {
 
 #ifndef NDEBUG
-	static char stderrbuff[512];
+	static char stderrbuff[BUFSIZ];
 
     if (Debug) {
 	codefile = stderr;