Prefer rb_error_arity to rb_check_arity when it can be used

eval.c

@@ -790,8 +790,7 @@ make_exception(int argc, const VALUE *argv, int isstr)
 	}
 	break;
       default:
-	rb_check_arity(argc, 0, 3);
+	rb_error_arity(argc, 0, 3);
-	break;
     }
     if (argc > 0) {
 	if (!rb_obj_is_kind_of(mesg, rb_eException))

file.c

@@ -3219,15 +3219,16 @@ rb_file_s_umask(int argc, VALUE *argv)
 {
     mode_t omask = 0;
 
-    if (argc == 0) {
+    switch (argc) {
+      case 0:
 	omask = umask(0);
 	umask(omask);
-    }
+        break;
-    else if (argc == 1) {
+      case 1:
 	omask = umask(NUM2MODET(argv[0]));
-    }
+        break;
-    else {
+      default:
-	rb_check_arity(argc, 0, 1);
+	rb_error_arity(argc, 0, 1);
     }
     return MODET2NUM(omask);
 }

numeric.c

@@ -3418,8 +3418,7 @@ int_chr(int argc, VALUE *argv, VALUE num)
       case 1:
 	break;
       default:
-	rb_check_arity(argc, 0, 1);
+	rb_error_arity(argc, 0, 1);
-	break;
     }
     enc = rb_to_encoding(argv[0]);
     if (!enc) enc = rb_ascii8bit_encoding();

string.c

@@ -5186,7 +5186,7 @@ str_gsub(int argc, VALUE *argv, VALUE str, int bang)
 	tainted = OBJ_TAINTED_RAW(repl);
 	break;
       default:
-	rb_check_arity(argc, 1, 2);
+	rb_error_arity(argc, 1, 2);
     }
 
     pat = get_pat_quoted(argv[0], 1);