The constructor is private, not the type.

Idea credit to @petrochenkov, discussed at rust-lang#65153

…r=GuillaumeGomez

Document missing deny by default lints

Implement Clone::clone_from for VecDeque

See rust-lang#28481. For simple data types with the target much longer than the source, this implementation can be significantly slower than the default (probably due to the use of truncate). However, it should be substantially faster when cloning from nested data structures with similar shapes or when cloning from VecDeques with similar lengths, hopefully more common use cases for clone_from.

Improve docs on some char boolean methods

simple revival of rust-lang#61794
(also rustfmt on rest of file :)

Documentation for `is_xid_start()` and `is_xid_continue()` couldn't be improved since both methods got remove from this repository

r? @dtolnay
cc @JohnCSimon

Suggest `if let` on `let` refutable binding

Fix rust-lang#58385.

…nkov

resolve: fix error title regarding private constructors

One reason is that constructors can be private while their types can be
public.

Idea credit to @petrochenkov, discussed at rust-lang#65153

Move diagnostics code out of the critical path

Follow up to rust-lang#65077.

r? @nnethercote

Report `CONST_ERR` lint in external macros

fixes rust-lang#65300
fixes rust-lang#61058

r? @oli-obk

…r=petrochenkov

replace the hand-written binary search with the library one

do not reference LLVM for our concurrency memory model

Fixes rust-lang#65282

…h-ascription, r=davidtwco

syntax: simplify maybe_annotate_with_ascription

Split out from rust-lang#65324.

r? @estebank

simplify maybe_stage_features

Extracted from rust-lang#65324.

r? @estebank

simplify integer_lit

Extracted from rust-lang#65324.

r? @davidtwco

mbe: reduce panictry! uses.

Extracted from rust-lang#65324.

r? @petrochenkov