Fix issue 21609 - LinearCongruentialEngine fails for m = 0

[Herringway]

No description provided.

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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	21609	normal	LinearCongruentialEngine fails for m = 0

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 "master + phobos#7786"

[berni44]

Looks like this is a hack around a bug in dmd. I filed a bug report Issue 21610. Maybe we should add a comment next to the static if, that this is a hack around this bug and could be reverted, when that bug is fixed.

If you like, you could also add a unittest, that guards against the typo in your first version, e.g. this:

@safe unittest
{
    alias LGE = LinearCongruentialEngine!(uint, 10000, 19682, 19683);

    LGE rnd;
    assert(rnd.front == 9999);
}

[Herringway]

Sounds good.