By default, closures inherit the generic parameters of their scope,
including `Self`. However, in most cases, the closures used to implement
iterators don't need to be generic on the iterator type, only its `Item`
type. We can reduce this genericity by redirecting such closures through
local functions.
This does make the closures more cumbersome to write, but it will
hopefully reduce duplication in their monomorphizations, as well as
their related type lengths.
Give built-in macros stable addresses in the standard library
Continuation of https://github.com/rust-lang/rust/pull/62086.
Derive macros corresponding to traits from libcore are now available through the same paths as those traits:
- `Clone` - `{core,std}::clone::Clone`
- `PartialEq` - `{core,std}::cmp::PartialEq`
- `Eq` - `{core,std}::cmp::Eq`
- `PartialOrd` - `{core,std}::cmp::PartialOrd`
- `Ord` - `{core,std}::cmp::Ord`
- `Default` - `{core,std}::default::Default`
- `Debug` - `{core,std}::fmt::Debug`
- `Hash` - `{core,std}:#️⃣:Hash`
- `Copy` - `{core,std}::marker::Copy`
Fn-like built-in macros are now available through libcore and libstd's root module, by analogy with non-builtin macros defined by libcore and libstd:
```rust
{core,std}::{
__rust_unstable_column,
asm,
assert,
cfg,
column,
compile_error,
concat,
concat_idents,
env,
file,
format_args,
format_args_nl,
global_asm,
include,
include_bytes,
include_str,
line,
log_syntax,
module_path,
option_env,
stringify,
trace_macros,
}
```
Derive macros without a corresponding trait in libcore or libstd are still available only through prelude (also see https://github.com/rust-lang/rust/pull/62507).
Attribute macros also keep being available only through prelude, mostly because they don't have an existing practice to follow. An advice from the library team on their eventual placement would be appreciated.
```rust
RustcDecodable,
RustcEncodable,
bench,
global_allocator,
test,
test_case,
```
r? @alexcrichton
enable flt2dec tests in Miri
With ldexp implemented (thanks to @christianpoveda), we can finally enable these tests in Miri. Well, most of them -- some are just too slow.
Remove gensym in format_args
This also fixes some things to allow us to export opaque macros from libcore:
* Don't consider items that are only reachable through opaque macros as public/exported (so they aren't linted as needing docs)
* Mark private items reachable from the root of libcore as unstable - they are now reachable (in principle) in other crates via macros in libcore
r? @petrochenkov
Improve `ptr_rotate` performance, tests, and benches
The corresponding issue is #61784. I am not actually sure if miri can handle the test, but I can change the commit if necessary.
move of packed fields might or might not occur when they actually are sufficiently aligned
See https://github.com/taiki-e/pin-project/pull/34, where it was pointed out that we actually don't move fields of 1-aligned types when dropping a packed struct -- but e.g. in a `packed(2)` struct, we don't do something similar for 2-aligned types. The code for that is [here](db7c773a6b/src/librustc_mir/util/alignment.rs (L7)).
