1 files changed, 1 insertions, 0 deletions
diff --git a/eval.c b/eval.c
index e60bcf2946..4a4c199c30 100644
--- a/eval.c
+++ b/eval.c
@@ -6106,6 +6106,7 @@ eval(self, src, scope, file, line)
 		errat = get_backtrace(ruby_errinfo);
 		mesg  = rb_attr_get(ruby_errinfo, rb_intern("mesg"));
 		if (!NIL_P(mesg) && TYPE(mesg) == T_STRING) {
+		    rb_str_update(mesg, 0, 0, rb_str_new2(": "));
 		    rb_str_update(mesg, 0, 0, RARRAY(errat)->ptr[0]);
 		}
 		RARRAY(errat)->ptr[0] = RARRAY(backtrace(-2))->ptr[0];