On 09/08/2024 17:34, Jakub Jelinek wrote:
> On Fri, Aug 09, 2024 at 04:21:14PM +0100, Alex Coplan wrote:
> > Hmm, good spot, I didn't realise that convert_from_reference could
> > change the type of the condition like this.
> >
> > In that case I suppose the only thing to do is to construct a stack of
> > ANNOTATE_EXPRs on the way down and re-build the expressions (taking the
> > type of the inner expression, starting with the cond) on the way back
> > up.
>
> I think you don't need to rebuild them, just update their types.
> Something along the lines of
> for (tree c = cond; c != *condp; c = TREE_OPERAND (c, 0))
> {
> gcc_checking_assert (TREE_CODE (c) == ANNOTATE_EXPR);
> TREE_TYPE (c) = TREE_TYPE (*condp);
> }
I suppose I was just concerned about any other properties of
ANNOTATE_EXPRs that might be inherited from the operand (that could be
affected by such a change).
It looks like TREE_{READONLY,THIS_VOLATILE,SIDE_EFFECTS} are all set
in convert_from_reference and propagated by build3, so if those change
underneath us then only updating the type seems insufficient.
>
> Jakub
>
