abort_internal is safe
`sys::abort_internal` is stably exposed as a safe function. Forward that assumption "inwards" to the `sys` module by making the function itself safe, too.
This corresponds to what https://github.com/rust-lang/rust/pull/72204 did for the intrinsic. We should probably wait until that lands because some of the intrinsic calls in this PR might then need adjustments.
use the new interface to initialize conditional variables
HermitCore introduce a new interface to intialize conditional variables.
Consequently, minor changes are required to support this interface.
make offset must_use
https://djugei.github.io/bad-at-unsafe/ describes an error a user had when trying to use offset:
> At first I just assumed that the .add() and .offset() methods on pointers would mutate the pointer. They do not. Instead they return a new pointer, which gets dropped silently if you don't use it. Unlike for example Result, which is must_use annotated.
This PR only adds `offset`, because I wanted to float the idea; I'm imagining that there's more than just `add` and `offset` that could use this. I am also very open to re-wording the warning.
r? @rust-lang/libs
Currently, if you repeatedly push to an empty vector, the capacity
growth sequence is 0, 1, 2, 4, 8, 16, etc. This commit changes the
relevant code (the "amortized" growth strategy) to skip 1 and 2 in most
cases, instead using 0, 4, 8, 16, etc. (You can still get a capacity of
1 or 2 using the "exact" growth strategy, e.g. via `reserve_exact()`.)
This idea (along with the phrase "tiny Vecs are dumb") comes from the
"doubling" growth strategy that was removed from `RawVec` in #72013.
That strategy was barely ever used -- only when a `VecDeque` was grown,
oddly enough -- which is why it was removed in #72013.
(Fun fact: until just a few days ago, I thought the "doubling" strategy
was used for repeated push case. In other words, this commit makes
`Vec`s behave the way I always thought they behaved.)
This change reduces the number of allocations done by rustc itself by
10% or more. It speeds up rustc, and will also speed up any other Rust
program that uses `Vec`s a lot.
move borrow-of-packed-field unsafety check out of loop
Looks like during the place refactoring, this code somehow got into this loop even though it does not actually depend on the loop variables.
https://djugei.github.io/bad-at-unsafe/ describes an error a user had when trying to use offset:
> At first I just assumed that the .add() and .offset() methods on pointers would mutate the pointer. They do not. Instead they return a new pointer, which gets dropped silently if you don't use it. Unlike for example Result, which is must_use annotated.
Disallow forbidden usage of non-ascii identifiers.
Part of RFC2457, this tightens allowed identifiers back to ascii only in two situations.
r? @petrochenkov
make abort intrinsic safe, and correct its documentation
Turns out `std::process::abort` is not the same as the intrinsic, the comment was just wrong. Quoting from the unix implementation:
```
// On Unix-like platforms, libc::abort will unregister signal handlers
// including the SIGABRT handler, preventing the abort from being blocked, and
// fclose streams, with the side effect of flushing them so libc buffered
// output will be printed. Additionally the shell will generally print a more
// understandable error message like "Abort trap" rather than "Illegal
// instruction" that intrinsics::abort would cause, as intrinsics::abort is
// implemented as an illegal instruction.
```
Rename lint `identity_conversion` to `useless_conversion`
Lint name `identity_conversion` was misleading, so this PR renames it to `useless_conversion`.
As decision has not really came up in the issue comments, this PR will probably need discussion.
fixes#3106
changelog: Rename lint `identity_conversion` to `useless_conversion`
