diff --git a/ChangeLog b/ChangeLog
index 2dc5065f77..452231eea1 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -3,6 +3,11 @@ Sun Aug 24 01:02:48 2003  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 	* file.c (file_expand_path): performance improvement.
 	  [ruby-talk:79748]
 
+Sat Aug 23 23:41:16 2003  Yukihiro Matsumoto  <matz@ruby-lang.org>
+
+	* file.c (rb_file_s_expand_path): avoid calling rb_scan_args() for
+	  apparent cases. [ruby-talk:79748]
+
 Sat Aug 23 18:56:53 2003  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* ext/nkf/nkf.c (rb_nkf_putchar): should use rb_str_resize() to just
diff --git a/eval.c b/eval.c
index 7f586a1e43..38edb34856 100644
--- a/eval.c
+++ b/eval.c
@@ -4256,16 +4256,13 @@ VALUE
 rb_yield_splat(values)
     VALUE values;
 {
-    VALUE tmp;
     int avalue = Qfalse;
 
-    tmp = rb_check_array_type(values);
-    if (!NIL_P(tmp)) {
-	if (RARRAY(tmp)->len == 0) {
+    if (TYPE(values) == T_ARRAY) {
+	if (RARRAY(values)->len == 0) {
 	    values = Qundef;
 	}
 	else {
-	    values = tmp;
 	    avalue = Qtrue;
 	}
     }
diff --git a/file.c b/file.c
index 223b243fc7..3a09b4e628 100644
--- a/file.c
+++ b/file.c
@@ -1758,6 +1758,10 @@ rb_file_s_expand_path(argc, argv)
     VALUE *argv;
 {
     VALUE fname, dname;
+
+    if (argc == 1) {
+	return rb_file_expand_path(argv[0], Qnil);
+    }
     rb_scan_args(argc, argv, "11", &fname, &dname);
 
     return rb_file_expand_path(fname, dname);