Re: [PATCH] c++, contracts: Only defer contracts that use an undeduced result binding [PR125537]

Hi Jason,

Thanks for the review.

On Tue, Aug 18, 2026 at 3:39 AM Jason Merrill <[email protected]> wrote:
>
> On 8/14/26 4:33 PM, Wang Jinghao wrote:
> > For precondition and postcondition without a result binding, whether
> > the return type is auto is irrelevant to the condition expression, so
> > type conversions should be completed immediately.
> >
> >       PR c++/125537
> >
> > gcc/cp/ChangeLog:
> >
> >       * pt.cc (tsubst_contract): Keep template processing enabled
> >       only for postconditions with an undeduced result binding.
>
> Hmm, I notice this is still a different condition from
> cp_parser_late_contract_condition and rebuild_postconditions, which only
> check whether there's a result binding, not whether it's auto.  They
> ought to agree on the condition for treating the postcondition as a
> pseudo-template.

If we also make the condition in cp_parser_late_contract_condition
consistent, we could even remove its call to rebuild_postconditions, since
the known-type path would no longer create pseudo-templates that require
this compensating step.

> > gcc/testsuite/ChangeLog:
> >
> >       * g++.dg/contracts/cpp26/pr125537.C: New test.
>
> Please name tests by what they are testing, not just by PR number.  So
> this could be template-post1.C.
>

All tests named using PR numbers in these patches will be renamed
appropriately in the v2 patches.

Best Regards,
Jinghao