https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82072
--- Comment #14 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
(In reply to Marek Polacek from comment #13)
> So maybe
>
> --- a/gcc/convert.c
> +++ b/gcc/convert.c
> @@ -886,6 +886,10 @@ convert_to_integer_1 (tree type, tree expr, bool dofold)
> break;
>
> case NEGATE_EXPR:
> + /* Using unsigned arithmetic may hide overflow bugs. */
> + if (sanitize_flags_p (SANITIZE_SI_OVERFLOW))
> + break;
> + /* Falls through. */
> case BIT_NOT_EXPR:
> /* This is not correct for ABS_EXPR,
> since we must test the sign before truncation. */
> @@ -902,12 +906,7 @@ convert_to_integer_1 (tree type, tree expr, bool dofold)
> TYPE_UNSIGNED (typex));
>
> if (!TYPE_UNSIGNED (typex))
> - {
> - /* Using unsigned arithmetic may hide overflow bugs. */
> - if (sanitize_flags_p (SANITIZE_SI_OVERFLOW))
> - break;
> - typex = unsigned_type_for (typex);
> - }
> + typex = unsigned_type_for (typex);
> return convert (type,
> fold_build1 (ex_form, typex,
> convert (typex,
Without checking if the inner type is signed? That would unnecessarily
penalize code where we have say:
unsigned long long l;
unsigned int i = -l;
or similar, no?
