Re: [PATCH RFA] asan: poisoning promoted statics [PR113531]

[Jason Merrill <jason@redhat.com>]

On 1/31/24 03:51, Richard Biener wrote:
> On Wed, Jan 31, 2024 at 4:38 AM Jason Merrill <jason@redhat.com> wrote:
>>
>> Tested x86_64-pc-linux-gnu, OK for trunk?
> 
> It's a quite "late" fixup, I suppose you have tried to avoid marking it
> during gimplification?  I see we do parts of this during BIND_EXPR
> processing which is indeed a bit early but possibly difficult to rectify.

I also considered

> diff --git a/gcc/gimplify.cc b/gcc/gimplify.cc
> index 7f79b3cc7e6..c906d927a09 100644
> --- a/gcc/gimplify.cc
> +++ b/gcc/gimplify.cc
> @@ -1249,6 +1249,10 @@ asan_poison_variable (tree decl, bool poison, gimple_stmt_iterator *it,
>    if (zerop (unit_size))
>      return;
> 
> +  /* Or variables in static storage.  */
> +  if (TREE_STATIC (decl))
> +    return;
> +
>    /* It's necessary to have all stack variables aligned to ASAN granularity
>       bytes.  */
>    gcc_assert (!hwasan_sanitize_p () || hwasan_sanitize_stack_p ());

which fixes the bug by avoiding the poison mark, but it's too late to 
avoid the unpoison mark--though the unpoison is still removed by sanopt, 
so the end result is the same.  I decided to send the other patch 
because it applies to both, but I'm happy with either approach.

Jason