First steps of late-bound turbofishing (place FnDef behind a dummy binder)

[addiesh]

r? oli-obk

This PR is part of #156581. This should be functionally identical to prior behavior, with the added fact that FnDef now places its arguments behind a binder.

most changes boil down to

• replacing args from FnDef with args.no_bound_vars().unwrap()
• replacing Ty::new_fn_def(/* ... */, args) with Ty::new_fn_def(/* ... */, ty::Binder::dummy(args))

[rustbot]

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[addiesh]

this change has nothing to do with LLVM and as such should probably not have A-LLVM

View changes since the review

[addiesh]

this PR probably shouldn't have as many tags as it does (A-LLVM, PG-exploit-mitigations, T-clippy, WG-trait-system-refactor)

[addiesh]

@rustbot review

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[rustbot]

Some changes occurred to the CTFE / Miri interpreter

cc @rust-lang/miri

Some changes occurred to the CTFE machinery

cc @RalfJung, @oli-obk, @lcnr

Some changes occurred to constck

cc @fee1-dead

changes to the core type system

cc @lcnr

Some changes occurred in compiler/rustc_sanitizers

cc @rcvalle

Some changes occurred to MIR optimizations

cc @rust-lang/wg-mir-opt

clippy is developed in its own repository. If possible, consider making this change to rust-lang/rust-clippy instead.

cc @rust-lang/clippy

This PR changes rustc_public

cc @oli-obk, @celinval, @ouz-a, @makai410

rustc_codegen_cranelift is developed in its own repository. If possible, consider making this change to rust-lang/rustc_codegen_cranelift instead.

cc @bjorn3

Some changes occurred in match checking

cc @Nadrieril

HIR ty lowering was modified

cc @fmease

Some changes occurred in match lowering

cc @Nadrieril