[php-src] Issue #8344: Attribute parameters cannot contain BackedEnum values

Issue: https://github.com/php/php-src/issues/8344 Comment Author: Crell I can't think of a good language argument to not allow En::Case->value (and I suppose also En::Case->name) in constant expressions. I could argue that it's a design flaw in an API, but that's a separate matter. If Nikita thinks it's safe them I'm fine with allowing it. I agree with others here that this sounds like an 8.2 feature. I also don't see a good reason to limit it to enums, when enums are really just sugar over objects to begin with. (new Foo)->value is very close to what's actually going on anyway. So yeah, my vote would be for allowing static -> de-references in constant expressions generally, as of 8.2. That... probably requires an RFC.