[PATCH, C] Fix format warnings

[Richard Guenther]

This patch makes the C frontend not warn that a format string
is not literal for things like

   char *a = "Foo";
   printf(&a[0]);

This will trigger everywhere in the format testsuite if the
C frontend starts emitting array-to-pointer decay as &a[0].

Compiled and tested on i686-unknown-linux for C.

Ok for mainline?

Thanks,
Richard.


2005-04-26  Richard Guenther  <rguenth@gcc.gnu.org>

	* c-format.c (check_format_arg): Handle &a[0] the same
	as &a.


Index: c-format.c
===================================================================
RCS file: /cvs/gcc/gcc/gcc/c-format.c,v
retrieving revision 1.73
diff -c -3 -p -r1.73 c-format.c
*** c-format.c	23 Apr 2005 21:27:31 -0000	1.73
--- c-format.c	26 Apr 2005 14:33:35 -0000
*************** check_format_arg (void *ctx, tree format
*** 1260,1265 ****
--- 1260,1268 ----
        return;
      }
    format_tree = TREE_OPERAND (format_tree, 0);
+   if (TREE_CODE (format_tree) == ARRAY_REF
+       && integer_zerop (TREE_OPERAND (format_tree, 1)))
+     format_tree = TREE_OPERAND (format_tree, 0);
    if (TREE_CODE (format_tree) == VAR_DECL
        && TREE_CODE (TREE_TYPE (format_tree)) == ARRAY_TYPE
        && (array_init = decl_constant_value (format_tree)) != format_tree