2010-04-29 Jon Grant <04@jguk.org>

[pf3gnuchains/gcc-fork.git] / gcc / c-typeck.c

diff --git a/gcc/c-typeck.c b/gcc/c-typeck.c
index df02975..96b2ab1 100644 (file)
--- a/gcc/c-typeck.c
+++ b/gcc/c-typeck.c
@@ -9503,6 +9503,46 @@ build_binary_op (location_t location, enum tree_code code,
          && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
              || code1 == FIXED_POINT_TYPE || code1 == COMPLEX_TYPE))
        short_compare = 1;
+      else if (code0 == POINTER_TYPE && null_pointer_constant_p (orig_op1))
+       {
+         if (TREE_CODE (op0) == ADDR_EXPR
+             && decl_with_nonnull_addr_p (TREE_OPERAND (op0, 0)))
+           {
+             if (code == EQ_EXPR)
+               warning_at (location,
+                           OPT_Waddress,
+                           "the comparison will always evaluate as %<false%> "
+                           "for the address of %qD will never be NULL",
+                           TREE_OPERAND (op0, 0));
+             else
+               warning_at (location,
+                           OPT_Waddress,
+                           "the comparison will always evaluate as %<true%> "
+                           "for the address of %qD will never be NULL",
+                           TREE_OPERAND (op0, 0));
+           }
+         result_type = type0;
+       }
+      else if (code1 == POINTER_TYPE && null_pointer_constant_p (orig_op0))
+       {
+         if (TREE_CODE (op1) == ADDR_EXPR
+             && decl_with_nonnull_addr_p (TREE_OPERAND (op1, 0)))
+           {
+             if (code == EQ_EXPR)
+               warning_at (location,
+                           OPT_Waddress, 
+                           "the comparison will always evaluate as %<false%> "
+                           "for the address of %qD will never be NULL",
+                           TREE_OPERAND (op1, 0));
+             else
+               warning_at (location,
+                           OPT_Waddress,
+                           "the comparison will always evaluate as %<true%> "
+                           "for the address of %qD will never be NULL",
+                           TREE_OPERAND (op1, 0));
+           }
+         result_type = type1;
+       }
       else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
        {
          tree tt0 = TREE_TYPE (type0);
@@ -9516,10 +9556,6 @@ build_binary_op (location_t location, enum tree_code code,
             and both must be object or both incomplete.  */
          if (comp_target_types (location, type0, type1))
            result_type = common_pointer_type (type0, type1);
-         else if (null_pointer_constant_p (orig_op0))
-           result_type = type1;
-         else if (null_pointer_constant_p (orig_op1))
-           result_type = type0;
          else if (!addr_space_superset (as0, as1, &as_common))
            {
              error_at (location, "comparison of pointers to "
@@ -9551,24 +9587,6 @@ build_binary_op (location_t location, enum tree_code code,
                              (build_qualified_type (void_type_node, qual));
            }
        }
-      else if (code0 == POINTER_TYPE && null_pointer_constant_p (orig_op1))
-       {
-         if (TREE_CODE (op0) == ADDR_EXPR
-             && decl_with_nonnull_addr_p (TREE_OPERAND (op0, 0)))
-           warning_at (location,
-                       OPT_Waddress, "the address of %qD will never be NULL",
-                       TREE_OPERAND (op0, 0));
-         result_type = type0;
-       }
-      else if (code1 == POINTER_TYPE && null_pointer_constant_p (orig_op0))
-       {
-         if (TREE_CODE (op1) == ADDR_EXPR
-             && decl_with_nonnull_addr_p (TREE_OPERAND (op1, 0)))
-           warning_at (location,
-                       OPT_Waddress, "the address of %qD will never be NULL",
-                       TREE_OPERAND (op1, 0));
-         result_type = type1;
-       }
       else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
        {
          result_type = type0;