From: Gabriel Dos Reis <gdr@integrable-solutions.net>
Date: Sun, 16 May 2004 22:52:19 +0000 (+0000)
Subject: backport: call.c (build_conditional_expr): Do not call force_rvalue for operands... 
X-Git-Tag: releases/gcc-3.3.4~33
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=956cde8f206024b3188041c508717a1d06cac2f5;p=thirdparty%2Fgcc.git

backport: call.c (build_conditional_expr): Do not call force_rvalue for operands of void_type when...

	Backport from mainline:
	2004-03-18  Mark Mitchell  <mark@codesourcery.com>
	* call.c (build_conditional_expr): Do not call force_rvalue for
	operands of void_type when the conditional expression itself
	has void type.

From-SVN: r81927
---

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 85adf271e050..b508b2fe5228 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,11 @@
+2004-05-16  Gabriel Dos Reis  <gdr@integrable-solutions.net>
+
+	Backport from mainline:
+	2004-03-18  Mark Mitchell  <mark@codesourcery.com>
+	* call.c (build_conditional_expr): Do not call force_rvalue for
+	operands of void_type when the conditional expression itself has
+	void type.
+
 2004-05-08  Kaveh R. Ghazi  <ghazi@caip.rutgers.edu>
 
 	* Make-lang.in (cp/init.o): Depend on diagnostic.h.
diff --git a/gcc/cp/call.c b/gcc/cp/call.c
index e45d5aaee0cc..313460b69845 100644
--- a/gcc/cp/call.c
+++ b/gcc/cp/call.c
@@ -3242,18 +3242,24 @@ build_conditional_expr (arg1, arg2, arg3)
 	   type of the other and is an rvalue.
 
 	 --Both the second and the third operands have type void; the
-	   result is of type void and is an rvalue.  */
+	   result is of type void and is an rvalue.  
+
+         We must avoid calling force_rvalue for expressions of type
+	 "void" because it will complain that their value is being
+	 used.   */
       if (TREE_CODE (arg2) == THROW_EXPR 
 	  && TREE_CODE (arg3) != THROW_EXPR)
 	{
-	  arg3 = force_rvalue (arg3);
+	  if (!VOID_TYPE_P (arg3_type))
+	    arg3 = force_rvalue (arg3);
 	  arg3_type = TREE_TYPE (arg3);
 	  result_type = arg3_type;
 	}
       else if (TREE_CODE (arg2) != THROW_EXPR 
 	       && TREE_CODE (arg3) == THROW_EXPR)
 	{
-	  arg2 = force_rvalue (arg2);
+	  if (!VOID_TYPE_P (arg2_type))
+	    arg2 = force_rvalue (arg2);
 	  arg2_type = TREE_TYPE (arg2);
 	  result_type = arg2_type;
 	}
diff --git a/gcc/testsuite/g++.dg/expr/cond5.C b/gcc/testsuite/g++.dg/expr/cond5.C
new file mode 100644
index 000000000000..cb62dd1cfa47
--- /dev/null
+++ b/gcc/testsuite/g++.dg/expr/cond5.C
@@ -0,0 +1,3 @@
+void f() {
+  true ? throw 1 : (void)7;
+}