On Mon, Sep 16, 2013 at 05:59:28PM +0200, Marek Polacek wrote:
> Regtested/ran bootstrap-ubsan on x86_64-linux.
That looks wrong. ubsan_type_descriptor shouldn't change TYPE_PRECISION of
the type it has been called with, whether type is a bitfield or not can
change what typedescriptor is generated, but not unrelated code.
> 2013-09-16 Marek Polacek <pola...@redhat.com>
>
> PR sanitizer/58413
> * ubsan.c (ubsan_type_descriptor): Change TYPE_PRECISION of
> a bit-field type to its TYPE_SIZE. Tweak type name.
>
> * c-c++-common/ubsan/shift-4.c: New test.
>
> --- gcc/ubsan.c.mp2 2013-09-16 16:55:26.653579402 +0200
> +++ gcc/ubsan.c 2013-09-16 16:57:29.192016988 +0200
> @@ -251,6 +251,10 @@ ubsan_type_descriptor (tree type)
> /* See through any typedefs. */
> type = TYPE_MAIN_VARIANT (type);
>
> + /* Handle bit-fields. */
> + if (compare_tree_int (TYPE_SIZE (type), TYPE_PRECISION (type) == 1))
> + TYPE_PRECISION (type) = tree_low_cst (TYPE_SIZE (type), 1);
> +
> tree decl = decl_for_type_lookup (type);
> if (decl != NULL_TREE)
> return decl;
> @@ -270,7 +274,7 @@ ubsan_type_descriptor (tree type)
> tname = IDENTIFIER_POINTER (DECL_NAME (TYPE_NAME (type)));
> }
> else
> - tname = "<unknown>";
> + tname = "<unnamed>";
>
> if (TREE_CODE (type) == INTEGER_TYPE)
> {
> --- gcc/testsuite/c-c++-common/ubsan/shift-4.c.mp2 2013-09-16
> 17:01:55.852982631 +0200
> +++ gcc/testsuite/c-c++-common/ubsan/shift-4.c 2013-09-16
> 17:32:32.114891611 +0200
> @@ -0,0 +1,14 @@
> +/* { dg-do run } */
> +/* { dg-options "-fsanitize=shift -w" } */
> +
> +struct S { unsigned long long int b:40; } s;
> +
> +int
> +main ()
> +{
> + s.b = 2;
> + s.b <<= 120;
> + return 0;
> +}
> +
> +/* { dg-output "shift exponent 120 is too large\[^\n\r]*(\n|\r\n|\r)" } */
>
> Marek
Jakub
