diff --git a/src/util.c b/src/util.c
index b195b51..9929586 100644
--- a/src/util.c
+++ b/src/util.c
@@ -165,7 +165,7 @@ FILE * xopen(const char * filename, const char * mode)
 {
   FILE * out = fopen(filename, mode);
   if (!out)
-    fatal("Cannot open file %s", opt_outfile);
+    fatal("Cannot open file %s", filename);
 
   return out;
 }