Fix Issue 20025 - alias this combined with a copy constructor seems to lead to undefined behaviour.

[RazvanN7]

No description provided.

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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	20025	normal	alias this combined with a copy constructor seems to lead to undefined behaviour.

Testing this PR locally

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

dub fetch digger
dub run digger -- build "stable + dmd#10137"

[ghost]

LGTM but can I suggest to target stable now that 2.087 is released ?

[RazvanN7]

@Basile-z done.

[ghost]

OK

[JinShil]

Indentation looks too deep.