From: Paolo Carlini <paolo.carlini@oracle.com>
Date: Wed, 28 Sep 2011 22:04:48 +0000 (+0000)
Subject: re PR c++/45278 (-Wextra doesn't warn about (pointer < 0 ).)
X-Git-Tag: releases/gcc-4.7.0~3484
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=6f94398e396918f4d244cc60991b1fc8f28941fc;p=thirdparty%2Fgcc.git

re PR c++/45278 (-Wextra doesn't warn about (pointer < 0 ).)

/cp
2011-09-28  Paolo Carlini  <paolo.carlini@oracle.com>

	PR c++/45278
	* typeck.c (cp_build_binary_op): With -Wextra, warn for ordered
	comparison of pointer with zero.

/testsuite
2011-09-28  Paolo Carlini  <paolo.carlini@oracle.com>

	PR c++/45278
	* g++.dg/warn/Wextra-3.C: New.

From-SVN: r179321
---

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 596d4a97f707..68e702fe8cf1 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,9 @@
+2011-09-28  Paolo Carlini  <paolo.carlini@oracle.com>
+
+	PR c++/45278
+	* typeck.c (cp_build_binary_op): With -Wextra, warn for ordered
+	comparison of pointer with zero.
+
 2011-09-27  Paolo Carlini  <paolo.carlini@oracle.com>
 
 	PR c++/31489
diff --git a/gcc/cp/typeck.c b/gcc/cp/typeck.c
index 10f17bf0494a..d416b42db3b0 100644
--- a/gcc/cp/typeck.c
+++ b/gcc/cp/typeck.c
@@ -4189,9 +4189,19 @@ cp_build_binary_op (location_t location,
 	result_type = composite_pointer_type (type0, type1, op0, op1,
 					      CPO_COMPARISON, complain);
       else if (code0 == POINTER_TYPE && null_ptr_cst_p (op1))
-	result_type = type0;
+	{
+	  result_type = type0;
+	  if (extra_warnings && (complain & tf_warning))
+	    warning (OPT_Wextra,
+		     "ordered comparison of pointer with integer zero");
+	}
       else if (code1 == POINTER_TYPE && null_ptr_cst_p (op0))
-	result_type = type1;
+	{
+	  result_type = type1;
+	  if (extra_warnings && (complain & tf_warning))
+	    warning (OPT_Wextra,
+		     "ordered comparison of pointer with integer zero");
+	}
       else if (null_ptr_cst_p (op0) && null_ptr_cst_p (op1))
 	/* One of the operands must be of nullptr_t type.  */
         result_type = TREE_TYPE (nullptr_node);
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index d19933a87469..ea1cad512019 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2011-09-28  Paolo Carlini  <paolo.carlini@oracle.com>
+
+	PR c++/45278
+	* g++.dg/warn/Wextra-3.C: New.
+
 2011-09-28  Oleg Endo  <oleg.endo@t-online.de>
 
 	PR target/49486
diff --git a/gcc/testsuite/g++.dg/warn/Wextra-3.C b/gcc/testsuite/g++.dg/warn/Wextra-3.C
new file mode 100644
index 000000000000..04fdbba9076f
--- /dev/null
+++ b/gcc/testsuite/g++.dg/warn/Wextra-3.C
@@ -0,0 +1,9 @@
+// PR c++/45278
+// { dg-options "-Wextra" } 
+
+extern void* p;
+
+int f1() { return ( p <  0 ? 1 : 0 ); } // { dg-warning "ordered comparison" }
+int f2() { return ( p <= 0 ? 1 : 0 ); } // { dg-warning "ordered comparison" }
+int f3() { return ( p >  0 ? 1 : 0 ); } // { dg-warning "ordered comparison" }
+int f4() { return ( p >= 0 ? 1 : 0 ); } // { dg-warning "ordered comparison" }