3c9a7491c2
Verify that `PartialEq` implementations do not break type inference when comparing types across different allocators. This catches a regression in current nightly introduced in 001b081cc1b (alloc: Allow comparing `Box`s over different allocators") `Box` is the only type that currently impelements this, but tests are included for `Rc` and `Arc` to prevent future regresssions.