ilya-biryukov added a comment. In D145639#4198794 <https://reviews.llvm.org/D145639#4198794>, @ChuanqiXu wrote:
> Reverting is common in Clang/LLVM. But let's wait for the response from > @bruno temporarily. I think it makes sense to revert this one if @bruno don't > response tomorrow. And we can commit this one and D145641 > <https://reviews.llvm.org/D145641> quickly the next time. Recommit is common > too. @bgraur, FYI, hope waiting for a day works for this case. In D145639#4198815 <https://reviews.llvm.org/D145639#4198815>, @ChuanqiXu wrote: >> The RVO seems to be mandated by the standard. > > Yeah, I thought so... But WG21 decided to not make it in a recent meeting... > So we can only make it as a non-mandated compiler optimization. That's unexpected. Are there any wording change proposals published? Our understanding comes from the reading of dcl.fct.def.coroutine/7 <https://timsong-cpp.github.io/cppwp/n4868/dcl.fct.def.coroutine#7> > The expression promise.get_return_object() is used to initialize the glvalue > result or prvalue result object of a call to a coroutine. And we **think** RVO is mandated when initializing the **result objects** mentioned in general. Also, from https://github.com/llvm/llvm-project/issues/56532: > Q: if the initialization does occur later, by what mechanism the prvalue > result of get_return_object is forwarded to that initialization. > A: (see below) > Case 1/2. Same type of get_return_object and coroutine return type. > **Constructed in the return slot.** > Case 3. Different types: > (1) Constructed temporary object prior to initial suspend initialized with a > call to get_return_object() > (2) when coroutine needs to to return to the caller and needs to construct > return value for the coroutine it is initialized with expiring value of the > temporary obtained in step 1. Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D145639/new/ https://reviews.llvm.org/D145639 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
