re PR c/40172 (Revision 147596 breaks bootstrap)

gcc/

2009-05-17  Manuel López-Ibáñez  <manu@gcc.gnu.org>

	PR c/40172
	* c-common.c (warn_logical_operator): Don't warn if one of
	expression isn't always true or false.

gcc/testscase/

2009-05-17  H.J. Lu  <hongjiu.lu@intel.com>

	PR c/40172
	* gcc.dg/pr40172.c: New.

From-SVN: r147639

gcc/ChangeLog

+2009-05-17  Manuel López-Ibáñez  <manu@gcc.gnu.org>
+
+	PR c/40172
+	* c-common.c (warn_logical_operator): Don't warn if one of
+	expression isn't always true or false.
+
 2009-05-17  Kai Tietz  <kai.tietz@onevision.com>
 
-       * config/i386/biarch32.h: New file.
-       * config.gcc: Add for target i386-w64-* the biarch32.h to tm_file.
+	* config/i386/biarch32.h: New file.
+	* config.gcc: Add for target i386-w64-* the biarch32.h to tm_file.
 
 2009-05-17  Adam Nemet  <anemet@caviumnetworks.com>
 

gcc/c-common.c

@@ -1784,10 +1784,8 @@ warn_logical_operator (location_t location, enum tree_code code, tree type,
     in0_p = !in0_p, in1_p = !in1_p;
   
   /* If both expressions are the same, if we can merge the ranges, and we
-     can build the range test, return it or it inverted.  If one of the
-     ranges is always true or always false, consider it to be the same
-     expression as the other.  */
-  if ((lhs == 0 || rhs == 0 || operand_equal_p (lhs, rhs, 0))
+     can build the range test, return it or it inverted.  */
+  if (lhs && rhs && operand_equal_p (lhs, rhs, 0)
       && merge_ranges (&in_p, &low, &high, in0_p, low0, high0,
 		       in1_p, low1, high1)
       && 0 != (tem = build_range_check (type,

gcc/testsuite/ChangeLog

+2009-05-17  H.J. Lu  <hongjiu.lu@intel.com>
+
+	PR c/40172
+	* gcc.dg/pr40172.c: New.
+
 2009-05-17  Jason Merrill  <jason@redhat.com>
 
 	PR c++/40139

gcc/testsuite/gcc.dg/pr40172.c

+/* PR middle-end/40172 */
+/* { dg-do compile } */
+/* { dg-options "-Wall -W -Werror" } */
+
+struct rtx_def;
+typedef struct rtx_def *rtx; 
+
+extern int foo;
+extern int bar;
+extern int xxx;
+
+int
+test (void)
+{
+  if (((rtx) 0 != (rtx) 0) && xxx ? foo : bar)
+    return 1;
+  else if ((foo & 0) && xxx)
+    return 2;
+  else if (foo & 0)
+    return 3;
+  else if (0 && xxx)
+    return 4;
+  else if (0)
+    return 5;
+  if (((int) 0 != (int) 0) && bar ? foo : xxx)
+    return 6;
+  else if (0 != 0 && foo ? xxx : bar)
+    return 7;
+  else
+    return 0;
+}