[Bug c++/115960] gcc throws an error when I use Optional in c++17.

[noahmartinwilliams at gmail dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115960

--- Comment #3 from Noah Williams <noahmartinwilliams at gmail dot com> ---
(In reply to Andrew Pinski from comment #2)
> Anyways this is not a GCC issue.
> 
> The   AttrBuilder::addAllocSizeAttr is declared in the preprocessed source
> as:
> AttrBuilder &addAllocSizeAttr(unsigned ElemSizeArg,
>                                 const std::optional<unsigned> &NumElemsArg);
> 
> But the upstream is defined as:
> 
>   AttrBuilder &addAllocSizeAttr(unsigned ElemSizeArg,
>                                 const Optional<unsigned> &NumElemsArg);
> 
> 
> https://github.com/hdoc/llvm-project/blob/
> a38b25fa77bdf1437c690494ae6d61179b3bb4f8/llvm/include/llvm/IR/Attributes.
> h#L1188
> 
> 
> Also note
> https://github.com/llvm/llvm-project/commit/
> 125f4457a54a550846732763ee36b1447ec8d66e
> 
> 
> Anyways this still not a GCC bug.

Darn. I was hoping this was a gcc bug since that would make fixing the llvm-hs
project easier. :(