Fix Bugzilla 24872 - Assigning non-copyable value to array has no effect

[pbackus]

Credit to @jacob-carlborg for pointing this out on Discord.

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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	24872	normal	Assigning non-copyable value to array has no effect

Testing this PR locally

If you don't have a local development environment setup, you can use Digger to test this PR:

dub run digger -- build "stable + dmd#17083"

[schveiguy]

Please target stable instead. This is a bug fix.

[pbackus]

Rebased and targeted to stable.

[thewilsonator]

std/array.d(307): Error: scope variable `r` may not be returned

???

[pbackus]

I was able to reproduce this failure locally using Phobos master and DMD stable, without this PR included. So I guess it's a DIP1000 bug in DMD stable that's fixed in master.

[thewilsonator]

If you could find what that is and cherry pick it that would be great.

[pbackus]

Bug was fixed by #16724

[pbackus]

Cherry-picking results in merge conflicts that I don't know the code well enough to resolve. Maybe @dkorpel can help?

[dkorpel]

The bug fix relies on refactoring (especially #16715) that's currently only in master, so either that refactoring has to be ported to stable as well, or the bug fix should be adapted to work in the code before refactoring. Or perhaps master can simply be merged into stable since 2.109.1 has been released, or was there a cutoff for 2.110 already? Not sure with the current release situation.