From patchwork Fri Dec  2 19:06:01 2011
Content-Type: text/plain; charset="utf-8"
MIME-Version: 1.0
Content-Transfer-Encoding: 7bit
Subject: [C++] PR 51313
Date: Fri, 02 Dec 2011 09:06:01 -0000
From: Paolo Carlini <paolo.carlini@oracle.com>
X-Patchwork-Id: 128936
Message-Id: <4ED92199.4040704@oracle.com>
To: "gcc-patches@gcc.gnu.org" <gcc-patches@gcc.gnu.org>
Cc: Jason Merrill <jason@redhat.com>

Hi,

here we ICE in C++11 mode in null_ptr_cst_p because integer_zerop is 
true for a NOP_EXPR, which TREE_OVERFLOW cannot handle. Thus the idea is 
using STRIP_NOPS in C++11 mode too: makes sense to me unless we have 
reasons of principle to exclude NOPs in that mode. Anyway, patch passes 
testing on x86_64-linux.

Thanks,
Paolo.

///////////////////////
/cp
2011-12-02  Paolo Carlini  <paolo.carlini@oracle.com>

	PR c++/51313
	* call.c (null_ptr_cst_p): STRIP_NOPS in c++11 mode too.

/testsuite
2011-12-02  Paolo Carlini  <paolo.carlini@oracle.com>

	PR c++/51313
	* g++.dg/cpp0x/pr51313.C: New.


Index: testsuite/g++.dg/cpp0x/pr51313.C
===================================================================
--- testsuite/g++.dg/cpp0x/pr51313.C	(revision 0)
+++ testsuite/g++.dg/cpp0x/pr51313.C	(revision 0)
@@ -0,0 +1,18 @@
+// PR c++/51313
+// { dg-options "-std=c++0x" }
+
+class ostream;
+
+extern "C" {
+  extern int isdigit (int);
+}
+
+ostream&
+operator<<(ostream&, const unsigned char*);
+
+extern ostream cout;
+
+int main()
+{
+  cout << isdigit(0);
+}
Index: cp/call.c
===================================================================
--- cp/call.c	(revision 181932)
+++ cp/call.c	(working copy)
@@ -549,10 +549,8 @@ null_ptr_cst_p (tree t)
     {
       /* Core issue 903 says only literal 0 is a null pointer constant.  */
       if (cxx_dialect < cxx0x)
-	{
-	  t = integral_constant_value (t);
-	  STRIP_NOPS (t);
-	}
+	t = integral_constant_value (t);
+      STRIP_NOPS (t);
       if (integer_zerop (t) && !TREE_OVERFLOW (t))
 	return true;
     }