[REG 1.42] Can supposedly index AA with mismatching key type

[kinke]

This fails with both beta1 and beta2 of LDC v1.42, but has worked with v1.41 and also works with DMD v2.112.0 and current DMD stable:

enum E { a }
bool[E] aa;
static assert(!__traits(compiles, aa[0])); // would compile since v1.42?!

Of course it wouldn't really compile:

core/internal/newaa.d(172): Error: cannot implicitly convert expression `key` of type `int` to `E`

Weird that this seems to be LDC-specific.

[kinke]

After a first quick scan of IN_LLVM frontend mods, I couldn't spot anything suspicious.

[kinke]

Oh, this might be a duplicate of dlang/dmd#22281, as I've cherry-picked dlang/dmd#22208 from DMD master (required to compile the Phobos unittests with -de IIRC), which seems to have introduced it.

[kinke]

Nope, apparently no duplicate, but another regression introduced in dlang/dmd#22208 - DMD master fails too.

[kinke]

Filed dlang/dmd#22560.