Assert that pthread mutex initialization succeeded
If pthread mutex initialization fails, the failure will go unnoticed unless
debug assertions are enabled. Any subsequent use of mutex will also silently
fail, since return values from lock & unlock operations are similarly checked
only through debug assertions.
In some implementations the mutex initialization requires a memory
allocation and so it does fail in practice.
Assert that initialization succeeds to ensure that mutex guarantees
mutual exclusion.
Fixes#34966.
The logging in compiletest was migrated from log crate to a tracing, but
the initialization code was never changed, so logging is non-functional.
Initialize tracing subscriber using default settings.
This optimization can result in unsoundness, because it introduces
additional uses of a place holding the discriminant value without
ensuring that it is valid to do so.
If pthread mutex initialization fails, the failure will go unnoticed unless
debug assertions are enabled. Any subsequent use of mutex will also silently
fail, since return values from lock & unlock operations are similarly checked
only through debug assertions.
In some implementations the mutex initialization requires a memory
allocation and so it does fail in practice.
Check that initialization succeeds to ensure that mutex guarantees
mutual exclusion.
Identical arguments on assert macro family
Lint when identical args are used on `assert_eq!`, `debug_assert_eq!`, `assert_ne!` and `debug_assert_ne!` macros.
Added to the lint `eq_op`.
Common functions added to `utils/higher.rs`
Fixes: #3574Fixes: #4694
changelog: Lint on identical args when calling `assert_eq!`, `debug_assert_eq!`, `assert_ne!` and `debug_assert_ne!` macros
Instead of trying to collect tokens at each depth, we 'flatten' the
stream as we go allong, pushing open/close delimiters to our buffer
just like regular tokens. One capturing is complete, we reconstruct a
nested `TokenTree::Delimited` structure, producing a normal
`TokenStream`.
The reconstructed `TokenStream` is not created immediately - instead, it is
produced on-demand by a closure (wrapped in a new `LazyTokenStream` type). This
closure stores a clone of the original `TokenCursor`, plus a record of the
number of calls to `next()/next_desugared()`. This is sufficient to reconstruct
the tokenstream seen by the callback without storing any additional state. If
the tokenstream is never used (e.g. when a captured `macro_rules!` argument is
never passed to a proc macro), we never actually create a `TokenStream`.
This implementation has a number of advantages over the previous one:
* It is significantly simpler, with no edge cases around capturing the
start/end of a delimited group.
* It can be easily extended to allow replacing tokens an an arbitrary
'depth' by just using `Vec::splice` at the proper position. This is
important for PR #76130, which requires us to track information about
attributes along with tokens.
* The lazy approach to `TokenStream` construction allows us to easily
parse an AST struct, and then decide after the fact whether we need a
`TokenStream`. This will be useful when we start collecting tokens for
`Attribute` - we can discard the `LazyTokenStream` if the parsed
attribute doesn't need tokens (e.g. is a builtin attribute).
The performance impact seems to be neglibile (see
https://github.com/rust-lang/rust/pull/77250#issuecomment-703960604). There is a
small slowdown on a few benchmarks, but it only rises above 1% for incremental
builds, where it represents a larger fraction of the much smaller instruction
count. There a ~1% speedup on a few other incremental benchmarks - my guess is
that the speedups and slowdowns will usually cancel out in practice.
Rollup of 4 pull requests
Successful merges:
- #77877 (Use `try{}` in `try_fold` to decouple iterators in the library from `Try` details)
- #78089 (Fix issue with specifying generic arguments for primitive types)
- #78099 (Add missing punctuation)
- #78103 (Add link to rustdoc book in rustdoc help popup)
Failed merges:
r? `@ghost`
Try to make ObligationForest more efficient
This PR tries to decrease the number of allocations in ObligationForest, as well as moves some cold path code to an uninlined function.
Suggest a compatible shell for setup-toolchain.sh
setup-toolchain.sh uses "[[" which is a bash builtin, but the guide
suggests running it with sh. On Ubuntu, /bin/sh points to dash and
running the script fails.
---
*Please keep the line below*
changelog: none
