Prefer rb_check_arity when 0 or 1 arguments

Especially over checking argc then calling rb_scan_args just to
raise an ArgumentError.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@66238 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 2 insertions, 1 deletions

diff --git a/vm.c b/vm.c
index 5920f25fc4..2c69498c13 100644
--- a/vm.c
+++ b/vm.c
@@ -422,7 +422,8 @@ vm_stat(int argc, VALUE *argv, VALUE self)
     VALUE arg = Qnil;
     VALUE hash = Qnil, key = Qnil;
 
-    if (rb_scan_args(argc, argv, "01", &arg) == 1) {
+    if (rb_check_arity(argc, 0, 1) == 1) {
+        arg = argv[0];
 	if (SYMBOL_P(arg))
 	    key = arg;
 	else if (RB_TYPE_P(arg, T_HASH))