diff --git a/lib/com_err/compile_et.c b/lib/com_err/compile_et.c
index 2cd747ecb..40934c055 100644
--- a/lib/com_err/compile_et.c
+++ b/lib/com_err/compile_et.c
@@ -56,7 +56,8 @@ char name[128];
 char Basename[128];
 
 #ifdef YYDEBUG
-extern int yydebug = 1;
+extern int yydebug;
+int yydebug = 1;
 #endif
 
 char *filename;