Fix Issue 20795 - [dip1000] segfault on templated opEquals

[RazvanN7]

sc.func is null when trying to call setUnsafe.

What puzzles me is that sc.func is used throughout the whole function without any checks. This makes me wonder if the check should be added at the start of the function.

[dlang-bot]

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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	20795	normal	[dip1000] segfault on templated opEquals

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#11096"

[thewilsonator]

Should this target stable?

[RazvanN7]

Bah, I always forget that....

Done.