re PR c/69768 (Bogus -Waddress warning)

	PR c/69768
	* c-typeck.c (parser_build_binary_op): Strip nops from integer_zerop
	arguments for -Waddress warning.

	* typeck.c (cp_build_binary_op): cp_fully_fold integer_zerop
	arguments for -Waddress warning.  Fix up formatting.

	* c-c++-common/Waddress-1.c: New test.

From-SVN: r233357

6 files changed, 42 insertions, 5 deletions

diff --git a/gcc/c/ChangeLog b/gcc/c/ChangeLog
index 931e51d..b595b81 100644
--- a/gcc/c/ChangeLog
+++ b/gcc/c/ChangeLog
@@ -1,3 +1,9 @@
+2016-02-11  Jakub Jelinek  <jakub@redhat.com>
+
+	PR c/69768
+	* c-typeck.c (parser_build_binary_op): Strip nops from integer_zerop
+	arguments for -Waddress warning.
+
 2016-02-04  Jakub Jelinek  <jakub@redhat.com>
 
 	PR c/69669
diff --git a/gcc/c/c-typeck.c b/gcc/c/c-typeck.c
index 65925cb..82efacf 100644
--- a/gcc/c/c-typeck.c
+++ b/gcc/c/c-typeck.c
@@ -3597,8 +3597,10 @@ parser_build_binary_op (location_t location, enum tree_code code,
      of testing for equality or inequality of a string literal with NULL.  */
   if (code == EQ_EXPR || code == NE_EXPR)
     {
-      if ((code1 == STRING_CST && !integer_zerop (arg2.value))
-	  || (code2 == STRING_CST && !integer_zerop (arg1.value)))
+      if ((code1 == STRING_CST
+	   && !integer_zerop (tree_strip_nop_conversions (arg2.value)))
+	  || (code2 == STRING_CST
+	      && !integer_zerop (tree_strip_nop_conversions (arg1.value))))
 	warning_at (location, OPT_Waddress,
 		    "comparison with string literal results in unspecified behavior");
     }
diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 7a80565..1b4ebd3 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,9 @@
+2016-02-11  Jakub Jelinek  <jakub@redhat.com>
+
+	PR c/69768
+	* typeck.c (cp_build_binary_op): cp_fully_fold integer_zerop
+	arguments for -Waddress warning.  Fix up formatting.
+
 2016-02-11  Paolo Carlini  <paolo.carlini@oracle.com>
 
 	PR c++/68726
diff --git a/gcc/cp/typeck.c b/gcc/cp/typeck.c
index c9fa112..3a247d8 100644
--- a/gcc/cp/typeck.c
+++ b/gcc/cp/typeck.c
@@ -4487,9 +4487,12 @@ cp_build_binary_op (location_t location,
 	warning (OPT_Wfloat_equal,
 		 "comparing floating point with == or != is unsafe");
       if ((complain & tf_warning)
-	  && ((TREE_CODE (orig_op0) == STRING_CST && !integer_zerop (op1))
-	      || (TREE_CODE (orig_op1) == STRING_CST && !integer_zerop (op0))))
-	warning (OPT_Waddress, "comparison with string literal results in unspecified behaviour");
+	  && ((TREE_CODE (orig_op0) == STRING_CST
+	       && !integer_zerop (cp_fully_fold (op1)))
+	      || (TREE_CODE (orig_op1) == STRING_CST
+		  && !integer_zerop (cp_fully_fold (op0)))))
+	warning (OPT_Waddress, "comparison with string literal results "
+			       "in unspecified behaviour");
 
       build_type = boolean_type_node;
       if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index c99f763..baf28f5 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2016-02-11  Jakub Jelinek  <jakub@redhat.com>
+
+	PR c/69768
+	* c-c++-common/Waddress-1.c: New test.
+
 2016-02-11  Andre Vehreschild  <vehre@gcc.gnu.org>
 
 	PR fortran/69296
diff --git a/gcc/testsuite/c-c++-common/Waddress-1.c b/gcc/testsuite/c-c++-common/Waddress-1.c
new file mode 100644
index 0000000..a5d128f
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/Waddress-1.c
@@ -0,0 +1,15 @@
+/* PR c/69768 */
+/* { dg-do compile } */
+/* { dg-options "-Waddress" } */
+
+static int e;
+
+int
+foo ()
+{
+  return "foo1" != (void *) 0	/* { dg-bogus "comparison with string literal results in unspecified behaviou?r" } */
+	 && "foo2" != (const char *) ((void *) 0)	/* { dg-bogus "comparison with string literal results in unspecified behaviou?r" } */
+	 && "foo3" != (const char *) ((void *) (10 - 10))	/* { dg-bogus "comparison with string literal results in unspecified behaviou?r" } */
+	 && "foo4" != (const char *) ((void *) (&e - &e))	/* { dg-warning "comparison with string literal results in unspecified behaviou?r" "" { target c } } */
+	 && "foo5" != "foo6";	/* { dg-warning "comparison with string literal results in unspecified behaviou?r" } */
+}