typeck.c (build_compound_expr): If RHS is a TARGET_EXPR, put the compound expr inside the target's initializer.

cp:
	* typeck.c (build_compound_expr): If RHS is a TARGET_EXPR, put the
	compound expr inside the target's initializer.
testsuite:
	* g++.dg/opt/tmp1.C: New test.

From-SVN: r70042

2 files changed, 16 insertions, 0 deletions

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 1bc4fed..d999173 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,5 +1,8 @@
 2003-08-01  Nathan Sidwell  <nathan@codesourcery.com>
 
+	* typeck.c (build_compound_expr): If RHS is a TARGET_EXPR, put the
+	compound expr inside the target's initializer.
+	
 	PR c++/11525
 	* parser.c (cp_parser_primary_expression): Do not set
 	non-constant-p merely because it is a dependent scope.
diff --git a/gcc/cp/typeck.c b/gcc/cp/typeck.c
index 00fa013..dd7e0af 100644
--- a/gcc/cp/typeck.c
+++ b/gcc/cp/typeck.c
@@ -4322,6 +4322,19 @@ build_compound_expr (tree lhs, tree rhs)
   lhs = convert_to_void (lhs, "left-hand operand of comma");
   if (lhs == error_mark_node || rhs == error_mark_node)
     return error_mark_node;
+
+  if (TREE_CODE (rhs) == TARGET_EXPR)
+    {
+      /* If the rhs is a TARGET_EXPR, then build the compound
+         expression inside the target_expr's initializer. This
+	 helps the compiler to eliminate unncessary temporaries.  */
+      tree init = TREE_OPERAND (rhs, 1);
+
+      init = build (COMPOUND_EXPR, TREE_TYPE (init), lhs, init);
+      TREE_OPERAND (rhs, 1) = init;
+      
+      return rhs;
+    }
   
   return build (COMPOUND_EXPR, TREE_TYPE (rhs), lhs, rhs);
 }