[PATCH] D128745: [c++] implements DR692, DR1395 and tentatively DR1432, about partial ordering of variadic template partial specialization or function template

Tue Oct 4 11:33:10 PDT 2022

ychen added a comment.

In D128745#3834387 <https://reviews.llvm.org/D128745#3834387>, @hubert.reinterpretcast wrote:

> In D128745#3834313 <https://reviews.llvm.org/D128745#3834313>, @ychen wrote:
>
>> I think the consensus is some flag is needed to put it back to legacy behavior just in case.
>
> I am not sure there is strong consensus to add a flag "just in case". Historically, many DRs had effects on overload resolution (via SFINAE or otherwise). Once we start adding flags "just in case", we might end up having a lot of them. These flags can exacerbate fracturing of the ecosystem.

New flag or not, as long as we allow users to use the old behavior, it is already fracturing the ecosystem. Do you mean (1) we shouldn't give the user the choices or  (2) we allow users to use the old behavior but only for a few releases and then remove the flag? I think (1) is a little bit harsh but I would say it is disruptive. (2) is more user-friendly.

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D128745/new/

https://reviews.llvm.org/D128745