eval.c: get rid of format-zero-length warning

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@62169 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

eval.c

@@ -641,7 +641,7 @@ rb_exc_fatal(VALUE mesg)
 void
 rb_interrupt(void)
 {
-    rb_raise(rb_eInterrupt, "");
+    rb_exc_raise(rb_exc_new(rb_eInterrupt, 0, 0));
 }
 
 enum {raise_opt_cause, raise_max_opt}; /*< \private */