From: Nathan Sidwell <nathan@codesourcery.com>
Date: Tue, 22 Oct 2002 09:06:19 +0000 (+0000)
Subject: re PR c++/7209 (Faulty array dereferencing)
X-Git-Tag: releases/gcc-3.2.1~123
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=0badb078c1b0b7ee0de83c36ae64aa5285199e03;p=thirdparty%2Fgcc.git

re PR c++/7209 (Faulty array dereferencing)

	PR c++/7209
	* fold_const.c (fold_binary_op_with_conditional_arg): Always
	build compound_expr if we used save_expr.
testsuite:
	* g++.dg/expr: New directory.
	* g++.dg/expr/cond1.C: New test.

From-SVN: r58406
---

diff --git a/gcc/fold-const.c b/gcc/fold-const.c
index f44c482379a0..926581c2ab47 100644
--- a/gcc/fold-const.c
+++ b/gcc/fold-const.c
@@ -4869,6 +4869,7 @@ fold_binary_op_with_conditional_arg (code, type, cond, arg, cond_first_p)
   /* And these are the types of the expressions.  */
   tree lhs_type = type;
   tree rhs_type = type;
+  int save = 0;
 
   if (cond_first_p)
     {
@@ -4927,11 +4928,12 @@ fold_binary_op_with_conditional_arg (code, type, cond, arg, cond_first_p)
      if an arm is a COND_EXPR since we get exponential behavior
      in that case.  */
   
-  if (TREE_CODE (arg) != SAVE_EXPR && ! TREE_CONSTANT (arg)
-      && global_bindings_p () == 0
-      && ((TREE_CODE (arg) != VAR_DECL
-	   && TREE_CODE (arg) != PARM_DECL)
-	  || TREE_SIDE_EFFECTS (arg)))
+  if (TREE_CODE (arg) == SAVE_EXPR)
+    save = 1;
+  else if (! TREE_CONSTANT (arg)
+	   && global_bindings_p () == 0
+	   && ((TREE_CODE (arg) != VAR_DECL && TREE_CODE (arg) != PARM_DECL)
+	       || TREE_SIDE_EFFECTS (arg)))
     {
       if (TREE_CODE (true_value) != COND_EXPR)
 	lhs = fold (build (lhs_code, lhs_type, *true_lhs, *true_rhs));
@@ -4941,7 +4943,11 @@ fold_binary_op_with_conditional_arg (code, type, cond, arg, cond_first_p)
       
       if ((lhs == 0 || ! TREE_CONSTANT (lhs))
 	  && (rhs == 0 || !TREE_CONSTANT (rhs)))
-	arg = save_expr (arg), lhs = rhs = 0;
+	{
+	  arg = save_expr (arg);
+	  lhs = rhs = 0;
+	  save = 1;
+	}
     }
   
   if (lhs == 0)
@@ -4951,7 +4957,7 @@ fold_binary_op_with_conditional_arg (code, type, cond, arg, cond_first_p)
   
   test = fold (build (COND_EXPR, type, test, lhs, rhs));
   
-  if (TREE_CODE (arg) == SAVE_EXPR)
+  if (save)
     return build (COMPOUND_EXPR, type,
 		  convert (void_type_node, arg),
 		  strip_compound_expr (test, arg));
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index ac6fb869f508..eacd9c3c2c0b 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,9 @@
+2002-10-22  Nathan Sidwell  <nathan@codesourcery.com>
+
+	PR c++/7209
+	* g++.dg/expr: New directory.
+	* g++.dg/expr/cond1.C: New test.
+
 2002-10-21  Zack Weinberg  <zack@codesourcery.com>
 
 	* gcc.dg/noncompile/920923-1.c: Prevent spurious regressions with