julia

625e8c7d - [JuliaLowering] Fix placeholders in parameters and decls, work around `hasmethod` (#60140)

[JuliaLowering] Fix placeholders in parameters and decls, work around `hasmethod` (#60140) Moved from https://github.com/c42f/JuliaLowering.jl/pull/99 ---- - Fix placeholders in positional and keyword arguments. - Placeholder positional arguments sometimes need to be read from due to the way we desugar keyword functions; give them an internal name. (fix https://github.com/c42f/JuliaLowering.jl/issue/55, port https://github.com/JuliaLang/julia/pull/58803) - Positional arguments may contain duplicate placeholders - Keywords may be placeholders (which is strange) but may not be duplicates - `kws...` may use a placeholder (fix https://github.com/c42f/JuliaLowering.jl/issue/49) - Allow placeholders in decls: `local`/`global _`, `local`/`global _::T`. This can be produced by destructuring assignments. I've implemented this to always drop the type (see https://github.com/JuliaLang/julia/issues/57497), but this may not be what we want. - Work around `hasmethod` always returning false for `world=typemax(UInt)` (some discussion [here](https://github.com/JuliaLang/julia/pull/59808)). I'm not sure we should be using `hasmethod` in the first place. - Comment out our `@atomic` implementation. We need to implement this for all forms that the normal `@atomic` takes, otherwise it hijacks the expansion and expects a simple form.