Replace absolute paths with relative ones
Modern compilers allow reaching external crates
like std or core via relative paths in modules
outside of lib.rs and main.rs.
Replace trivial bool matches with the `matches!` macro
This derives `PartialEq` on one enum (and two structs it contains) to enable the `==` operator for it. If there's some downside to this, I could respin with the `matches!` macro instead.
Use tracing spans in rustc_trait_selection
Spans are very helpful when debugging this code. It's also hot enough to make a good benchmark.
r? `@oli-obk`
Mono collector: replace pair of ints with Range
I found the initial PR (#33171) that introduced this piece of code but I didn't find any information about why a tuple was preferred over a `Range<usize>`.
I'm hoping there are no technical reasons to not do this.
Remove unnecessary unsafe block around calls to discriminant_value
Since 63793 the discriminant_value intrinsic is safe to call. Remove
unnecessary unsafe block around calls to this intrinsic in built-in
derive macros.
Use llvm::computeLTOCacheKey to determine post-ThinLTO CGU reuse
During incremental ThinLTO compilation, we attempt to re-use the
optimized (post-ThinLTO) bitcode file for a module if it is 'safe' to do
so.
Up until now, 'safe' has meant that the set of modules that our current
modules imports from/exports to is unchanged from the previous
compilation session. See PR #67020 and PR #71131 for more details.
However, this turns out be insufficient to guarantee that it's safe
to reuse the post-LTO module (i.e. that optimizing the pre-LTO module
would produce the same result). When LLVM optimizes a module during
ThinLTO, it may look at other information from the 'module index', such
as whether a (non-imported!) global variable is used. If this
information changes between compilation runs, we may end up re-using an
optimized module that (for example) had dead-code elimination run on a
function that is now used by another module.
Fortunately, LLVM implements its own ThinLTO module cache, which is used
when ThinLTO is performed by a linker plugin (e.g. when clang is used to
compile a C proect). Using this cache directly would require extensive
refactoring of our code - but fortunately for us, LLVM provides a
function that does exactly what we need.
The function `llvm::computeLTOCacheKey` is used to compute a SHA-1 hash
from all data that might influence the result of ThinLTO on a module.
In addition to the module imports/exports that we manually track, it
also hashes information about global variables (e.g. their liveness)
which might be used during optimization. By using this function, we
shouldn't have to worry about new LLVM passes breaking our module re-use
behavior.
In LLVM, the output of this function forms part of the filename used to
store the post-ThinLTO module. To keep our current filename structure
intact, this PR just writes out the mapping 'CGU name -> Hash' to a
file. To determine if a post-LTO module should be reused, we compare
hashes from the previous session.
This should unblock PR #75199 - by sheer chance, it seems to have hit
this issue due to the particular CGU partitioning and optimization
decisions that end up getting made.
Recognize discriminant reads as no-ops in RemoveNoopLandingPads
The cleanup blocks often contain read of discriminants. Teach
RemoveNoopLandingPads to recognize them as no-ops to remove
additional no-op landing pads.
Add -Z codegen-backend dylib to deps
When the codegen-backend dylib changes, the program should be rebuilt.
---
Unfortunately I was unable to test this works locally due to running into a TLS issue when running the custom backend, `thread 'rustc' panicked at 'no ImplicitCtxt stored in tls', compiler/rustc_middle/src/ty/context.rs:1750:54`, which seems similar to https://github.com/rust-lang/rust/issues/62717 but has a completely different cause and backtrace.
`@eddyb` said to ping `@Mark-Simulacrum` about what they think about this, so, ping!
Since 63793 the discriminant_value intrinsic is safe to call. Remove
unnecessary unsafe block around calls to this intrinsic in built-in
derive macros.
Provide structured suggestions when finding structs when expecting a trait
When finding an ADT in a trait object definition provide some solutions. Fix#45817.
Given `<Param as Trait>::Assoc: Ty` suggest `Param: Trait<Assoc = Ty>`. Fix#75829.
Allow generic parameters in intra-doc links
Fixes#62834.
---
The contents of the generics will be mostly ignored (except for warning
if fully-qualified syntax is used, which is currently unsupported in
intra-doc links - see issue #74563).
* Allow links like `Vec<T>`, `Result<T, E>`, and `Option<Box<T>>`
* Allow links like `Vec::<T>::new()`
* Warn on
* Unbalanced angle brackets (e.g. `Vec<T` or `Vec<T>>`)
* Missing type to apply generics to (`<T>` or `<Box<T>>`)
* Use of fully-qualified syntax (`<Vec as IntoIterator>::into_iter`)
* Invalid path separator (`Vec:<T>:new`)
* Too many angle brackets (`Vec<<T>>`)
* Empty angle brackets (`Vec<>`)
Note that this implementation *does* allow some constructs that aren't
valid in the actual Rust syntax, for example `Box::<T>new()`. That may
not be supported in rustdoc in the future; it is an implementation
detail.
They were not formatted correctly, so rustdoc was interpreting some
parts as code. Also cleaned up some other query docs that weren't
causing issues, but were formatted incorrectly.
