* compile.c (NODE_ARGSCAT, NODE_ARGSPUSH): drop unused ARGSCAT

results when poped is true.  [ruby-dev:41933], [Bug #3658]
  This is retry of r28870 and r28873 which were reverted.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@28877 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ChangeLog

@@ -1,3 +1,9 @@
+Thu Aug  5 21:20:31 2010  Yusuke Endoh  <mame@tsg.ne.jp>
+
+	* compile.c (NODE_ARGSCAT, NODE_ARGSPUSH): drop unused ARGSCAT
+	  results when poped is true.  [ruby-dev:41933], [Bug #3658]
+	  This is retry of r28870 and r28873 which were reverted.
+
 Thu Aug  5 20:13:49 2010  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* README.EXT, README.EXT.ja (String functions): mention

compile.c

@@ -4521,16 +4521,34 @@ iseq_compile_each(rb_iseq_t *iseq, LINK_ANCHOR *ret, NODE * node, int poped)
 	break;
       }
       case NODE_ARGSCAT:{
-	COMPILE(ret, "argscat head", node->nd_head);
-	COMPILE(ret, "argscat body", node->nd_body);
-	ADD_INSN(ret, nd_line(node), concatarray);
+	if (poped) {
+	    COMPILE(ret, "argscat head", node->nd_head);
+	    ADD_INSN1(ret, nd_line(node), splatarray, Qfalse);
+	    ADD_INSN(ret, nd_line(node), pop);
+	    COMPILE(ret, "argscat body", node->nd_body);
+	    ADD_INSN1(ret, nd_line(node), splatarray, Qfalse);
+	    ADD_INSN(ret, nd_line(node), pop);
+	}
+	else {
+	    COMPILE(ret, "argscat head", node->nd_head);
+	    COMPILE(ret, "argscat body", node->nd_body);
+	    ADD_INSN(ret, nd_line(node), concatarray);
+	}
 	break;
       }
       case NODE_ARGSPUSH:{
-	COMPILE(ret, "arsgpush head", node->nd_head);
-	COMPILE(ret, "argspush body", node->nd_body);
-	ADD_INSN1(ret, nd_line(node), newarray, INT2FIX(1));
-	ADD_INSN(ret, nd_line(node), concatarray);
+	if (poped) {
+	    COMPILE(ret, "arsgpush head", node->nd_head);
+	    ADD_INSN1(ret, nd_line(node), splatarray, Qfalse);
+	    ADD_INSN(ret, nd_line(node), pop);
+	    COMPILE_(ret, "argspush body", node->nd_body, poped);
+	}
+	else {
+	    COMPILE(ret, "arsgpush head", node->nd_head);
+	    COMPILE_(ret, "argspush body", node->nd_body, poped);
+	    ADD_INSN1(ret, nd_line(node), newarray, INT2FIX(1));
+	    ADD_INSN(ret, nd_line(node), concatarray);
+	}
 	break;
       }
       case NODE_SPLAT:{

test/ruby/test_primitive.rb

@@ -400,4 +400,24 @@ class TestRubyPrimitive < Test::Unit::TestCase
     #assert_equal [0,1,2,3,4], [0, *a, 4]
   end
 
+  def test_concatarray_ruby_dev_41933
+    bug3658 = '[ruby-dev:41933]'
+    [0, *x=1]
+    assert_equal(1, x, bug3658)
+    [0, *x=1, 2]
+    assert_equal(1, x, bug3658)
+    class << (x = Object.new)
+      attr_accessor :to_a_called
+      def to_a
+        @to_a_called = true
+        [self]
+      end
+    end
+    x.to_a_called = false
+    [0, *x]
+    assert(x.to_a_called, bug3658)
+    x.to_a_called = false
+    [0, *x, 2]
+    assert(x.to_a_called, bug3658)
+  end
 end