Fix issue 16244 - Prevent an ICE with empty cast

[LemonBoy]

No description provided.

[dlang-bot]

Fix	Bugzilla	Description
✓	16244	compiler ICE on complex typeof() for method arg type

[UplinkCoder]

This looks okay.

[UplinkCoder]

e.error here ?

[LemonBoy]

Hm? A cast with no type is semantically valid albeit just a no-op

[UplinkCoder]

then maybe we can warn ?
uint a = cast()12;
does indeed compile but I feel it's strange to allow that

[UplinkCoder]

@LemonBoy where does it say that an empty cast is semantically valid ?

[dnadlinger]

@UplinkCoder: Grammatically, it is valid as per the second clause of CastExpression, and the semantics (remove any type modifiers) are documented in the spec.

[UplinkCoder]

@klickverbot I'd say we should fix the spec then this makes no sense what-so-ever.

[dnadlinger]

@UplinkCoder: It's quite useful to cast away const/shared/…, and there on purpose. Just because you don't know a part of the language doesn't mean it "makes no sense what-so-ever".

[UplinkCoder]

@klickverbot then it is not a no-op. but rather a buitin cast-to-unqual.

[dnadlinger]

then it is not a no-op. but rather a buitin cast-to-unqual.

Indeed – I was just replying to your question, and missed @LemonBoy's no-op suggestion.

[LemonBoy]

Rebased, the DAutoTest failure looks unrelated.
Can we somehow get this merged?

[UplinkCoder]

@andralex this is ready.