[SAoC 2023] Replace DRuntime Hooks with Templates Weekly Update #5

[Teodor Dutu]

Hi,

This week I took a deeper look into my fix for [this 
bug](https://issues.dlang.org/show_bug.cgi?id=24159). It involves 
storing the lowering in a new field within `CatAssignExp` (called 
`lowering`). It previously ran into a backend error that turned 
out to be caused by incorrectly inlining the lowering instead of 
the `CatAssignExp`. The lowering could not be inlined as often as 
the original expression.

With this out of the way, I am now facing another error during 
CTFE as it cannot interpret the lowering. But similarly to the 
backend error from earlier, CTFE shouldn't interpret this 
lowering. Now I am trying to skip this step and interpret the 
right thing instead.

In addition, the [PR for converting `_d_newarray{U,iT,T}` to 
templates](https://github.com/dlang/dmd/pull/15299) was merged 
and a discussion arose about including it in the changelog. I'm 
not sure about this, so I created [this 
PR](https://github.com/dlang/dmd/pull/15729) to add a changelog 
entry about the template `_d_newarrayT`. If you have any opinions 
on this, let's discuss them there.

Thanks,
Teodor