ICE on completely bogus use of `ref` in closure parameter list

[ben0x539]

I was overly optimistic regarding rustc's current DWIM semantics, and rustc didn't even know how to exhaustively describe my stupidity.

foo.rs:1:22: 1:28 error: the type of this value must be known in this context
foo.rs:1 fn main() { |ref x| { x += 1; }; }
                               ^~~~~~
error: internal compiler error: no type for node 9: expr 1 (id=9) in fcx 7f86d428df40

[nikomatsakis]

Yeah, interesting! We should probably prevent ref modes in argument patterns altogether.

[ben0x539]

The original example doesn't seem to throw an ICE anymore. The following still crashes the compiler:

fn main() { 
    let _f: &fn(int) -> int = |ref x: int| { *x };
}

rustc: /home/ben/code/repos/rust/src/llvm/include/llvm/Support/Casting.h:197: typename llvm::cast_retty<To, From>::ret_type llvm::cast(const Y&) [with X = llvm::PointerType; Y = llvm::Type_; typename llvm::cast_retty<To, From>::ret_type = llvm::PointerType_]: Assertion `isa(Val) && "cast() argument of incompatible type!"' failed.
Aborted

Seems to be a bit uncertain whether my bogus parameter is a pointer or not.

[emberian]

New example still reproduces:

rustc: ../../../../../src/llvm/include/llvm/Support/Casting.h:231: typename enable_if<is_same<Y, typename simplify_type<Y>::SimpleType>, typename cast_retty<X, Y *>::ret_type>::type llvm::cast(Y *) [X = llvm::PointerType, Y = llvm::Type]: Assertion `isa<X>(Val) && "cast<Ty>() argument of incompatible type!"' failed.
zsh: abort (core dumped)  rustc foo.rs

[metajack]

This was apparently fixed. Closing.

[emberian]

Reopening, needstest.