The ARMv5te platform does not have instruction-level support for atomics, however the kernel provides [user space helpers](https://www.kernel.org/doc/Documentation/arm/kernel_user_helpers.txt) which can be used to perform atomic operations. When linked with `libc`, the atomic symbols needed by Rust will be provided, rather than CPU level intrinsics.
As this target is specifically `linux` and `gnueabi`, it is reasonable to assume the Linux Kernel and libc will be available for the target. There is a large performance penalty, as we are not using CPU level intrinsics, however this penalty is likely preferable to not having the target at all.
I have used this change in a custom target (along with `xargo`) to build `std`, as well as a number of higher level crates.
Mir pretty print: Add cleanup comment
I found it useful to add a comment indicating whether or not a
BasicBlock is a cleanup block or not. Hopefully you'll find it
useful too.
Docs for size_of::<#[repr(C)]> items.
Most of this info comes from camlorn's blog post on optimizing struct layout and the Rustonomicon.
I don't really like my wording in the first paragraph.
I also cannot find a definition of what `#[repr(C)]` does for enums that have variants with fields. They're allowed, unlike `#[repr(C)] enum`s with no variants.
This commit makes two main changes.
1. It switches the spsc_queue node caching strategy from keeping a shared
counter of the number of nodes in the cache to keeping a consumer only counter
of the number of node eligible to be cached.
2. It separate the consumer and producers fields of spsc_queue and stream into
a producer cache line and consumer cache line.
Fix native main() signature on 64bit
Hello,
in LLVM-IR produced by rustc on x86_64-linux-gnu, the native main() function had incorrect types for the function result and argc parameter: i64, while it should be i32 (really c_int). See also #20064, #29633.
So I've attempted a fix here. I tested it by checking the LLVM IR produced with --target x86_64-unknown-linux-gnu and i686-unknown-linux-gnu. Also I tried running the tests (`./x.py test`), however I'm getting two failures with and without the patch, which I'm guessing is unrelated.
Update the libcompiler_builtins submodule
Pulls in the latest changes from libcompiler_builtins.
It should work, but it would be best if this wouldn't get put into a rollup so that bisecting is possible if there is a regression.
r? @alexcrichton
Docs: Add trace_macros! to unstable book
As TIL'd at Rustfest :)
Note: This is unfortunately untested, since I'm on my laptop battery, and compiling LLVM would probably eat at least 50% of it on my dual core CPU. (Is there a way to build docs without compiling LLVM?)
rustc: Enable LTO and multiple codegen units
This commit is a refactoring of the LTO backend in Rust to support compilations
with multiple codegen units. The immediate result of this PR is to remove the
artificial error emitted by rustc about `-C lto -C codegen-units-8`, but longer
term this is intended to lay the groundwork for LTO with incremental compilation
and ultimately be the underpinning of ThinLTO support.
The problem here that needed solving is that when rustc is producing multiple
codegen units in one compilation LTO needs to merge them all together.
Previously only upstream dependencies were merged and it was inherently relied
on that there was only one local codegen unit. Supporting this involved
refactoring the optimization backend architecture for rustc, namely splitting
the `optimize_and_codegen` function into `optimize` and `codegen`. After an LLVM
module has been optimized it may be blocked and queued up for LTO, and only
after LTO are modules code generated.
Non-LTO compilations should look the same as they do today backend-wise, we'll
spin up a thread for each codegen unit and optimize/codegen in that thread. LTO
compilations will, however, send the LLVM module back to the coordinator thread
once optimizations have finished. When all LLVM modules have finished optimizing
the coordinator will invoke the LTO backend, producing a further list of LLVM
modules. Currently this is always a list of one LLVM module. The coordinator
then spawns further work to run LTO and code generation passes over each module.
In the course of this refactoring a number of other pieces were refactored:
* Management of the bytecode encoding in rlibs was centralized into one module
instead of being scattered across LTO and linking.
* Some internal refactorings on the link stage of the compiler was done to work
directly from `CompiledModule` structures instead of lists of paths.
* The trans time-graph output was tweaked a little to include a name on each
bar and inflate the size of the bars a little
The innermost type is not [u8] on all platforms but is assumed to have
the same memory layout as [u8] since this conversion was done via
mem::transmute before.
remove FIXME(#13101) since `assert_receiver_is_total_eq` stays.
remove FIXME(#19649) now that stability markers render.
remove FIXME(#13642) now the benchmarks were moved.
remove FIXME(#6220) now that floating points can be formatted.
remove FIXME(#18248) and write tests for `Rc<str>` and `Rc<[u8]>`
remove reference to irelevent issues in FIXME(#1697, #2178...)
update FIXME(#5516) to point to getopts issue 7
update FIXME(#7771) to point to RFC 628
update FIXME(#19839) to point to issue 26925
This commit is a refactoring of the LTO backend in Rust to support compilations
with multiple codegen units. The immediate result of this PR is to remove the
artificial error emitted by rustc about `-C lto -C codegen-units-8`, but longer
term this is intended to lay the groundwork for LTO with incremental compilation
and ultimately be the underpinning of ThinLTO support.
The problem here that needed solving is that when rustc is producing multiple
codegen units in one compilation LTO needs to merge them all together.
Previously only upstream dependencies were merged and it was inherently relied
on that there was only one local codegen unit. Supporting this involved
refactoring the optimization backend architecture for rustc, namely splitting
the `optimize_and_codegen` function into `optimize` and `codegen`. After an LLVM
module has been optimized it may be blocked and queued up for LTO, and only
after LTO are modules code generated.
Non-LTO compilations should look the same as they do today backend-wise, we'll
spin up a thread for each codegen unit and optimize/codegen in that thread. LTO
compilations will, however, send the LLVM module back to the coordinator thread
once optimizations have finished. When all LLVM modules have finished optimizing
the coordinator will invoke the LTO backend, producing a further list of LLVM
modules. Currently this is always a list of one LLVM module. The coordinator
then spawns further work to run LTO and code generation passes over each module.
In the course of this refactoring a number of other pieces were refactored:
* Management of the bytecode encoding in rlibs was centralized into one module
instead of being scattered across LTO and linking.
* Some internal refactorings on the link stage of the compiler was done to work
directly from `CompiledModule` structures instead of lists of paths.
* The trans time-graph output was tweaked a little to include a name on each
bar and inflate the size of the bars a little
Remove new and index methods already implement for Idx
These are the rest of the repeated implementations for new and index methods. Follow up of https://github.com/rust-lang/rust/pull/44889
Normalize spaces in lang attributes.
So, like, I grepped for all `lang` attributes for *reasons* and I noticed that they all share the same spacing of `#[lang = "item_name"]` except these five instances. So I decided to fix that. So enjoy this PR of exactly ten spaces.
Improve wording for StepBy
No other iterator makes the distinction between an iterator and an iterator adapter
in its summary line, so change it to be consistent with all other adapters.
docs improvement std::sync::{PoisonError, TryLockError}
Addresses the `PoisonError` and `TryLockError` parts of #29377.
Adds examples and links.
r? @steveklabnik
adding E0623 for return types - both parameters are anonymous
This is a fix for #44018
```
error[E0621]: explicit lifetime required in the type of `self`
--> $DIR/ex3-both-anon-regions-return-type-is-anon.rs:17:5
|
16 | fn foo<'a>(&self, x: &i32) -> &i32 {
| ---- ----
| |
| this parameter and the return type are
declared with different lifetimes...
17 | x
| ^ ...but data from `x` is returned here
error: aborting due to previous error
```
It also works for the below case where we have self as anonymous
```
error[E0623]: lifetime mismatch
--> src/test/ui/lifetime-errors/ex3-both-anon-regions-self-is-anon.rs:17:19
|
16 | fn foo<'a>(&self, x: &Foo) -> &Foo {
| ---- ----
| |
| this parameter and the return type are
declared with different lifetimes...
17 | if true { x } else { self }
| ^ ...but data from `x` is returned here
error: aborting due to previous error
```
r? @nikomatsakis
Currently, I have enabled E0621 where return type and self are anonymous, hence WIP.
Add blanket TryFrom impl when From is implemented.
Adds `impl<T, U> TryFrom<T> for U where U: From<T>`.
Removes `impl<'a, T> TryFrom<&'a str> for T where T: FromStr` (originally added in #40281) due to overlapping impls caused by the new blanket impl. This removal is to be discussed further on the tracking issue for TryFrom.
Refs #33417.
/cc @sfackler, @scottmcm (thank you for the help!), and @aturon
First step toward implementing impl Trait in argument position
First step implementing #44721.
Add a flag to hir and ty TypeParameterDef and raise an error when using
explicit type parameters when calling a function using impl Trait in
argument position.
I don't know if there is a procedure to add an error code so I just took an available code. Is that ok ?
r? @nikomatsakis
Add more custom folding to `core::iter` adaptors
Many of the iterator adaptors will perform faster folds if they forward
to their inner iterator's folds, especially for inner types like `Chain`
which are optimized too. The following types are newly specialized:
| Type | `fold` | `rfold` |
| ----------- | ------ | ------- |
| `Enumerate` | ✓ | ✓ |
| `Filter` | ✓ | ✓ |
| `FilterMap` | ✓ | ✓ |
| `FlatMap` | exists | ✓ |
| `Fuse` | ✓ | ✓ |
| `Inspect` | ✓ | ✓ |
| `Peekable` | ✓ | N/A¹ |
| `Skip` | ✓ | N/A² |
| `SkipWhile` | ✓ | N/A¹ |
¹ not a `DoubleEndedIterator`
² `Skip::next_back` doesn't pull skipped items at all, but this couldn't
be avoided if `Skip::rfold` were to call its inner iterator's `rfold`.
Benchmarks
----------
In the following results, plain `_sum` computes the sum of a million
integers -- note that `sum()` is implemented with `fold()`. The
`_ref_sum` variants do the same on a `by_ref()` iterator, which is
limited to calling `next()` one by one, without specialized `fold`.
The `chain` variants perform the same tests on two iterators chained
together, to show a greater benefit of forwarding `fold` internally.
test iter::bench_enumerate_chain_ref_sum ... bench: 2,216,264 ns/iter (+/- 29,228)
test iter::bench_enumerate_chain_sum ... bench: 922,380 ns/iter (+/- 2,676)
test iter::bench_enumerate_ref_sum ... bench: 476,094 ns/iter (+/- 7,110)
test iter::bench_enumerate_sum ... bench: 476,438 ns/iter (+/- 3,334)
test iter::bench_filter_chain_ref_sum ... bench: 2,266,095 ns/iter (+/- 6,051)
test iter::bench_filter_chain_sum ... bench: 745,594 ns/iter (+/- 2,013)
test iter::bench_filter_ref_sum ... bench: 889,696 ns/iter (+/- 1,188)
test iter::bench_filter_sum ... bench: 667,325 ns/iter (+/- 1,894)
test iter::bench_filter_map_chain_ref_sum ... bench: 2,259,195 ns/iter (+/- 353,440)
test iter::bench_filter_map_chain_sum ... bench: 1,223,280 ns/iter (+/- 1,972)
test iter::bench_filter_map_ref_sum ... bench: 611,607 ns/iter (+/- 2,507)
test iter::bench_filter_map_sum ... bench: 611,610 ns/iter (+/- 472)
test iter::bench_fuse_chain_ref_sum ... bench: 2,246,106 ns/iter (+/- 22,395)
test iter::bench_fuse_chain_sum ... bench: 634,887 ns/iter (+/- 1,341)
test iter::bench_fuse_ref_sum ... bench: 444,816 ns/iter (+/- 1,748)
test iter::bench_fuse_sum ... bench: 316,954 ns/iter (+/- 2,616)
test iter::bench_inspect_chain_ref_sum ... bench: 2,245,431 ns/iter (+/- 21,371)
test iter::bench_inspect_chain_sum ... bench: 631,645 ns/iter (+/- 4,928)
test iter::bench_inspect_ref_sum ... bench: 317,437 ns/iter (+/- 702)
test iter::bench_inspect_sum ... bench: 315,942 ns/iter (+/- 4,320)
test iter::bench_peekable_chain_ref_sum ... bench: 2,243,585 ns/iter (+/- 12,186)
test iter::bench_peekable_chain_sum ... bench: 634,848 ns/iter (+/- 1,712)
test iter::bench_peekable_ref_sum ... bench: 444,808 ns/iter (+/- 480)
test iter::bench_peekable_sum ... bench: 317,133 ns/iter (+/- 3,309)
test iter::bench_skip_chain_ref_sum ... bench: 1,778,734 ns/iter (+/- 2,198)
test iter::bench_skip_chain_sum ... bench: 761,850 ns/iter (+/- 1,645)
test iter::bench_skip_ref_sum ... bench: 478,207 ns/iter (+/- 119,252)
test iter::bench_skip_sum ... bench: 315,614 ns/iter (+/- 3,054)
test iter::bench_skip_while_chain_ref_sum ... bench: 2,486,370 ns/iter (+/- 4,845)
test iter::bench_skip_while_chain_sum ... bench: 633,915 ns/iter (+/- 5,892)
test iter::bench_skip_while_ref_sum ... bench: 666,926 ns/iter (+/- 804)
test iter::bench_skip_while_sum ... bench: 444,405 ns/iter (+/- 571)
rustc: Default 32 codegen units at O0
This commit changes the default of rustc to use 32 codegen units when compiling
in debug mode, typically an opt-level=0 compilation. Since their inception
codegen units have matured quite a bit, gaining features such as:
* Parallel translation and codegen enabling codegen units to get worked on even
more quickly.
* Deterministic and reliable partitioning through the same infrastructure as
incremental compilation.
* Global rate limiting through the `jobserver` crate to avoid overloading the
system.
The largest benefit of codegen units has forever been faster compilation through
parallel processing of modules on the LLVM side of things, using all the cores
available on build machines that typically have many available. Some downsides
have been fixed through the features above, but the major downside remaining is
that using codegen units reduces opportunities for inlining and optimization.
This, however, doesn't matter much during debug builds!
In this commit the default number of codegen units for debug builds has been
raised from 1 to 32. This should enable most `cargo build` compiles that are
bottlenecked on translation and/or code generation to immediately see speedups
through parallelization on available cores.
Work is being done to *always* enable multiple codegen units (and therefore
parallel codegen) but it requires #44841 at least to be landed and stabilized,
but stay tuned if you're interested in that aspect!
Point at signature on unused lint
```
warning: struct is never used: `Struct`
--> $DIR/unused-warning-point-at-signature.rs:22:1
|
22 | struct Struct {
| ^^^^^^^^^^^^^
```
Fix#33961.
The local address's port is not 8080 in this example, that's the remote peer address port. On my machine, the local address is different every time, so I've changed `assert_eq` to only test the IP address
To match the C signature, main() should be generated with C int type
for the argc parameter and result, i.e. i32 instead of i64 on 64bit.
That way it no longer relies on the upper 32 bits being zero, which I'm
not sure is guaranteed by ABIs or startup code.
Allow replacing HashMap entries
This is an obvious API hole. At the moment the only way to retrieve an entry from a `HashMap` is to get an entry to it, remove it, and then insert a new entry. This PR allows entries to be replaced.
TrustedRandomAccess specialisation for Iterator::cloned when Item: Copy.
This should fix#44424. It also provides a potential fix for more iterators using `Iterator::cloned`.
Add aarch64-unknown-linux-musl target
This adds support for the aarch64-unknown-linux-musl target in the build and CI systems.
This addresses half of issue #42520.
The new file `aarch64_unknown_linux_musl.rs` is a copy of `aarch64_unknown_linux_gnu.rs` with "gnu" replaced by "musl", and the added logic in `build-arm-musl.sh` is similarly a near-copy of the arches around it, so overall the changes were straightforward.
Testing:
```
$ sudo ./src/ci/docker/run.sh cross
...
Dist std stage2 (x86_64-unknown-linux-gnu -> aarch64-unknown-linux-musl)
Building stage2 test artifacts (x86_64-unknown-linux-gnu -> aarch64-unknown-linux-musl)
Compiling getopts v0.2.14
Compiling term v0.0.0 (file:///checkout/src/libterm)
Compiling test v0.0.0 (file:///checkout/src/libtest)
Finished release [optimized] target(s) in 16.91 secs
Copying stage2 test from stage2 (x86_64-unknown-linux-gnu -> x86_64-unknown-linux-gnu / aarch64-unknown-linux-musl)
...
Build completed successfully in 0:55:22
```
```
$ rustup toolchain link local obj/build/x86_64-unknown-linux-gnu/stage2
$ rustup default local
```
After setting the local toolchain as default, and adding this in ~/.cargo/config:
```
[target.aarch64-unknown-linux-musl]
linker = "aarch64-linux-musl-gcc"
```
...then the toolchain was able to build a working ripgrep as a test:
```
$ readelf -a target/aarch64-unknown-linux-musl/debug/rg | grep -i interpreter
$ readelf -a target/aarch64-unknown-linux-musl/debug/rg | grep NEEDED
$ file target/aarch64-unknown-linux-musl/debug/rg
target/aarch64-unknown-linux-musl/debug/rg: ELF 64-bit LSB executable, ARM aarch64, version 1 (GNU/Linux), statically linked, BuildID[sha1]=be11036b0988fac5dccc9f6487eb780b05186582, not stripped
```
On Windows with the NTFS filesystem, `fs::copy` would return the sum of the
lengths of all streams, which can be different from the length reported by
`metadata` and thus confusing for users unaware of this NTFS peculiarity.
This makes `fs::copy` return the same length `metadata` reports which is the
value it used to return before PR #26751. Note that alternate streams are still
copied; their length is just not included in the returned value.
This change relies on the assumption that the stream with index 1 is always the
main stream in the `CopyFileEx` callback. I could not find any official
document confirming this but empirical testing has shown this to be true,
regardless of whether the alternate stream is created before or after the main
stream.
Resolves#44532
Point at parameter type on E0301
On "the parameter type `T` may not live long enough" error, point to the
parameter type suggesting lifetime bindings:
```
error[E0310]: the parameter type `T` may not live long enough
--> $DIR/lifetime-doesnt-live-long-enough.rs:28:5
|
27 | struct Foo<T> {
| - help: consider adding an explicit lifetime bound `T: 'static`...
28 | foo: &'static T
| ^^^^^^^^^^^^^^^
|
note: ...so that the reference type `&'static T` does not outlive the data it points at
--> $DIR/lifetime-doesnt-live-long-enough.rs:28:5
|
28 | foo: &'static T
| ^^^^^^^^^^^^^^^
```
Fix#36700.
Initial support for `..=` syntax
#28237
This PR adds `..=` as a synonym for `...` in patterns and expressions.
Since `...` in expressions was never stable, we now issue a warning.
cc @durka
r? @aturon
Allow unused extern crate again
This is a partial revert of #42588. There is a usability concern reported in #44294 that was not considered in the discussion of the PR, so I would like to back this out of 1.21. As is, I think users would have a worse and more confusing experience with this lint enabled by default. We can re-enabled once there are better diagnostics or the case in #44294 does not trigger the lint.
Fix capacity comparison in reserve
You can otherwise end up in a situation where you don't actually resize
but still call into handle_cap_increase which then corrupts head/tail.
Closes#44800
Not totally sure the right way to write a test for this - there are some debug asserts the old bad behavior will hit but we don't build the stdlib with debug assertions by default.
r? @Gankro
use param_env on the trait_cache key
We bailed from making trans_fulfill_obligation return `Option` or `Result`, just made it less prone to crashing outside trans
r? @nikomatsakis
Add a flag to hir and ty TypeParameterDef and raise an error when using
explicit type parameters when calling a function using impl Trait in
argument position.
This commit changes the default of rustc to use 32 codegen units when compiling
in debug mode, typically an opt-level=0 compilation. Since their inception
codegen units have matured quite a bit, gaining features such as:
* Parallel translation and codegen enabling codegen units to get worked on even
more quickly.
* Deterministic and reliable partitioning through the same infrastructure as
incremental compilation.
* Global rate limiting through the `jobserver` crate to avoid overloading the
system.
The largest benefit of codegen units has forever been faster compilation through
parallel processing of modules on the LLVM side of things, using all the cores
available on build machines that typically have many available. Some downsides
have been fixed through the features above, but the major downside remaining is
that using codegen units reduces opportunities for inlining and optimization.
This, however, doesn't matter much during debug builds!
In this commit the default number of codegen units for debug builds has been
raised from 1 to 32. This should enable most `cargo build` compiles that are
bottlenecked on translation and/or code generation to immediately see speedups
through parallelization on available cores.
Work is being done to *always* enable multiple codegen units (and therefore
parallel codegen) but it requires #44841 at least to be landed and stabilized,
but stay tuned if you're interested in that aspect!
Some fixes to mir-borrowck
Make the code more closely match the NLL RFC (updated description).
(The biggest visible fix the addition of the Shallow/Deep distinction, which means mir-borrowck stops falsely thinking that StorageDeads need deep access to their input L-value.)
Many of the iterator adaptors will perform faster folds if they forward
to their inner iterator's folds, especially for inner types like `Chain`
which are optimized too. The following types are newly specialized:
| Type | `fold` | `rfold` |
| ----------- | ------ | ------- |
| `Enumerate` | ✓ | ✓ |
| `Filter` | ✓ | ✓ |
| `FilterMap` | ✓ | ✓ |
| `FlatMap` | exists | ✓ |
| `Fuse` | ✓ | ✓ |
| `Inspect` | ✓ | ✓ |
| `Peekable` | ✓ | N/A¹ |
| `Skip` | ✓ | N/A² |
| `SkipWhile` | ✓ | N/A¹ |
¹ not a `DoubleEndedIterator`
² `Skip::next_back` doesn't pull skipped items at all, but this couldn't
be avoided if `Skip::rfold` were to call its inner iterator's `rfold`.
Benchmarks
----------
In the following results, plain `_sum` computes the sum of a million
integers -- note that `sum()` is implemented with `fold()`. The
`_ref_sum` variants do the same on a `by_ref()` iterator, which is
limited to calling `next()` one by one, without specialized `fold`.
The `chain` variants perform the same tests on two iterators chained
together, to show a greater benefit of forwarding `fold` internally.
test iter::bench_enumerate_chain_ref_sum ... bench: 2,216,264 ns/iter (+/- 29,228)
test iter::bench_enumerate_chain_sum ... bench: 922,380 ns/iter (+/- 2,676)
test iter::bench_enumerate_ref_sum ... bench: 476,094 ns/iter (+/- 7,110)
test iter::bench_enumerate_sum ... bench: 476,438 ns/iter (+/- 3,334)
test iter::bench_filter_chain_ref_sum ... bench: 2,266,095 ns/iter (+/- 6,051)
test iter::bench_filter_chain_sum ... bench: 745,594 ns/iter (+/- 2,013)
test iter::bench_filter_ref_sum ... bench: 889,696 ns/iter (+/- 1,188)
test iter::bench_filter_sum ... bench: 667,325 ns/iter (+/- 1,894)
test iter::bench_filter_map_chain_ref_sum ... bench: 2,259,195 ns/iter (+/- 353,440)
test iter::bench_filter_map_chain_sum ... bench: 1,223,280 ns/iter (+/- 1,972)
test iter::bench_filter_map_ref_sum ... bench: 611,607 ns/iter (+/- 2,507)
test iter::bench_filter_map_sum ... bench: 611,610 ns/iter (+/- 472)
test iter::bench_fuse_chain_ref_sum ... bench: 2,246,106 ns/iter (+/- 22,395)
test iter::bench_fuse_chain_sum ... bench: 634,887 ns/iter (+/- 1,341)
test iter::bench_fuse_ref_sum ... bench: 444,816 ns/iter (+/- 1,748)
test iter::bench_fuse_sum ... bench: 316,954 ns/iter (+/- 2,616)
test iter::bench_inspect_chain_ref_sum ... bench: 2,245,431 ns/iter (+/- 21,371)
test iter::bench_inspect_chain_sum ... bench: 631,645 ns/iter (+/- 4,928)
test iter::bench_inspect_ref_sum ... bench: 317,437 ns/iter (+/- 702)
test iter::bench_inspect_sum ... bench: 315,942 ns/iter (+/- 4,320)
test iter::bench_peekable_chain_ref_sum ... bench: 2,243,585 ns/iter (+/- 12,186)
test iter::bench_peekable_chain_sum ... bench: 634,848 ns/iter (+/- 1,712)
test iter::bench_peekable_ref_sum ... bench: 444,808 ns/iter (+/- 480)
test iter::bench_peekable_sum ... bench: 317,133 ns/iter (+/- 3,309)
test iter::bench_skip_chain_ref_sum ... bench: 1,778,734 ns/iter (+/- 2,198)
test iter::bench_skip_chain_sum ... bench: 761,850 ns/iter (+/- 1,645)
test iter::bench_skip_ref_sum ... bench: 478,207 ns/iter (+/- 119,252)
test iter::bench_skip_sum ... bench: 315,614 ns/iter (+/- 3,054)
test iter::bench_skip_while_chain_ref_sum ... bench: 2,486,370 ns/iter (+/- 4,845)
test iter::bench_skip_while_chain_sum ... bench: 633,915 ns/iter (+/- 5,892)
test iter::bench_skip_while_ref_sum ... bench: 666,926 ns/iter (+/- 804)
test iter::bench_skip_while_sum ... bench: 444,405 ns/iter (+/- 571)
Add suggestions for misspelled method names
Use the syntax::util::lev_distance module to provide suggestions when a
named method cannot be found.
Part of #30197
Require rlibs for dependent crates when linking static executables
This handles the case for `CrateTypeExecutable` and `+crt_static`. I reworked the match block to avoid duplicating the `attempt_static` and error checking code again (this case would have been a copy of the `CrateTypeCdylib`/`CrateTypeStaticlib` case).
On `linux-musl` targets where `std` was built with `crt_static = false` in `config.toml`, this change brings the test suite from entirely failing to mostly passing.
This change should not affect behavior for other crate types, or for targets which do not respect `+crt_static`.
Allow writing metadata without llvm
# Todo:
* [x] Rebase
* [x] Fix eventual errors
* [x] <strike>Find some crate to write elf files</strike> (will do it later)
Cc #43842
No other iterator makes the distinction between an iterator and an iterator adapter
in its summary line, so change it to be consistent with all other adapters.
encode region::Scope using fewer bytes
Now that region::Scope is no longer interned, its size is more important. This PR encodes region::Scope in 8 bytes instead of 12, which should speed up region inference somewhat (perf testing needed) and should improve the margins on #36799 by 64MB (that's not a lot, I did this PR mostly to speed up region inference).
This is a perf-sensitive PR. Please don't roll me up.
r? @eddyb
This is based on #44743 so I could get more accurate measurements on #36799.
In particular:
* introduce the shallow/deep distinction for read/write accesses
* use the notions of prefixes, shallow prefixes, and supporting prefixes
rather than trying to recreate the restricted sets from ast-borrowck.
* Add shallow reads of Discriminant and ArrayLength, and treat them
as artificial fields when doing prefix traversals.
This is a partial revert of #42588. There is a usability concern
reported in #44294 that was not considered in the discussion of the PR,
so I would like to back this out of 1.21. As is, I think users would
have a worse and more confusing experience with this lint enabled by
default. We can re-enabled once there are better diagnostics or the case
in #44294 does not trigger the lint.
* Adjust bootstrap to provide useful output on failure
* Add missing package dependencies in the build environment
* Fix permission bits on prebuilt toolchain files
Move effect-checking to MIR
This allows emitting lints from MIR and moves the effect-checking pass to work on it.
I'll make `repr(packed)` misuse unsafe in a separate PR.
r? @eddyb
put empty generic lists behind a pointer
This reduces the size of hir::Expr from 128 to 88 bytes (!) and shaves
200MB out of #36799.
This is a performance-sensitive PR so please don't roll it up.
r? @eddyb
On "the parameter type `T` may not live long enough" error, point to the
parameter type suggesting lifetime bindings:
```
error[E0310]: the parameter type `T` may not live long enough
--> $DIR/lifetime-doesnt-live-long-enough.rs:28:5
|
27 | struct Foo<T> {
| - help: consider adding an explicit lifetime bound `T: 'static`...
28 | foo: &'static T
| ^^^^^^^^^^^^^^^
|
note: ...so that the reference type `&'static T` does not outlive the data it points at
--> $DIR/lifetime-doesnt-live-long-enough.rs:28:5
|
28 | foo: &'static T
| ^^^^^^^^^^^^^^^
```
The convention for suggesting close matches is to provide at most one match (the
closest one). Change the suggestions for misspelt method names to obey that.
typeck::check::coercion - roll back failed unsizing type vars
This wraps unsizing coercions within an additional level of
`commit_if_ok`, which rolls back type variables if the unsizing coercion
fails. This prevents a large amount of type-variables from accumulating
while type-checking a large function, e.g. shaving 2GB off one of the
4GB peaks in #36799.
This is a performance-sensitive PR so please don't roll it up.
r? @eddyb
cc @nikomatsakis
Now that region::Scope is no longer interned, its size is more
important. This PR encodes region::Scope in 8 bytes instead of 12, which
should speed up region inference somewhat (perf testing needed) and
should improve the margins on #36799 by 64MB (that's not a lot, I did
this PR mostly to speed up region inference).
add comparison operators to must-use lint (under `fn_must_use` feature)
Although RFC 1940 is about annotating functions with `#[must_use]`, a
key part of the motivation was linting unused equality operators.
(See
https://github.com/rust-lang/rfcs/pull/1812#issuecomment-265695898—it
seems to have not been clear to discussants at the time that marking the
comparison methods as `must_use` would not give us the lints on
comparison operators, at least in (what the present author understood
as) the most straightforward implementation, as landed in #43728
(3645b062).)
To rectify the situation, we here lint unused comparison operators as
part of the unused-must-use lint (feature gated by the `fn_must_use`
feature flag, which now arguably becomes a slight (tolerable in the
opinion of the present author) misnomer).
This is in the matter of #43302.
cc @crumblingstatue
This wraps unsizing coercions within an additional level of
`commit_if_ok`, which rolls back type variables if the unsizing coercion
fails. This prevents a large amount of type-variables from accumulating
while type-checking a large function, e.g. shaving 2GB off one of the
4GB peaks in #36799.
Improve diagnostics when attempting to match tuple enum variant with struct pattern
Adds an extra note as below to explain that a tuple pattern was probably intended.
```
error[E0026]: variant `X::Y` does not have a field named `data`
--> src/main.rs:18:16
|
18 | X::Y { data } => println!("The data is {}", data)
| ^^^^ variant `X::Y` does not have field `data`
error[E0027]: pattern does not mention field `0`
--> src/main.rs:18:9
|
18 | X::Y { data } => println!("The data is {}", data)
| ^^^^^^^^^^^^^ missing field `0`
|
= note: trying to match a tuple variant with a struct variant pattern
```
Fixes#41314.
You can otherwise end up in a situation where you don't actually resize
but still call into handle_cap_increase which then corrupts head/tail.
Closes#44800
incr.comp.: Add new DepGraph implementation.
This commits does a few things:
1. It adds the new dep-graph implementation -- *in addition* to the old one. This way we can start testing the new implementation without switching all tests at once.
2. It persists the new dep-graph (which includes query result fingerprints) to the incr. comp. caching directory and also loads this data.
3. It removes support for loading fingerprints of metadata imported from other crates (except for when running autotests). This is not needed anymore with red/green. It could provide a performance advantage but that's yet to be determined. For now, as red/green is not fully implemented yet, the cross-crate incremental tests are disabled.
Note, this PR is based on top of soon-to-be-merged #44696 and only the last 4 commits are new:
```
- incr.comp.: Initial implemenation of append-only dep-graph. (c90147c)
- incr.comp.: Do some various cleanup. (8ce20c5)
- incr.comp.: Serialize and deserialize new DepGraph. (0e13c1a)
- incr.comp.: Remove support for loading metadata fingerprints. (270a134)
EDIT 2:
- incr.comp.: Make #[rustc_dirty/clean] test for fingerprint equality ... (d8f7ff9)
```
(EDIT: GH displays the commits in the wrong order for some reason)
Also note that this PR is expected to certainly result in performance regressions in the incr. comp. test cases, since we are adding quite a few things (a whole additional dep-graph, for example) without removing anything. End-to-end performance measurements will only make sense again after red/green is enabled and all the legacy tracking has been turned off.
EDIT 2: Pushed another commit that makes the `#[rustc_dirty]`/`#[rustc_clean]` based autotests compared query result fingerprints instead of testing `DepNode` existence.
This verifies that TrustedRandomAccess has no side effects when the
iterator item implements Copy. This also implements TrustedLen and
TrustedRandomAccess for str::Bytes.
Record semantic types for all syntactic types in bodies
... and use recorded types in type privacy checking (types are recorded after inference, so there are no `_`s left).
Also use `hir_ty_to_ty` for types in signatures in type privacy checking.
This could also be potentially useful for save-analysis and diagnostics.
Fixes https://github.com/rust-lang/rust/pull/42125#issuecomment-305987755
r? @eddyb
std::sync::RwLock docs improvement
Addresses the `RwLock` part of #29377.
r? @steveklabnik
Added examples, links to types, and a small comparison between RwLock and Mutex.
Less confusing placeholder when RefCell is exclusively borrowed
Based on ExpHP's comment in [*RefCell.borrow_mut get strange result*](https://users.rust-lang.org/t/refcell-borrow-mut-get-strange-result/12994):
> it would perhaps be nicer if it didn't put something that could be misinterpreted as a valid string value
The previous Debug implementation would show:
RefCell { value: "<borrowed>" }
The new one is:
RefCell { value: <borrowed> }
rustc: Don't use DelimToken::None if possible
This commit fixes a regression from #44601 where lowering attribute to HIR now
involves expanding interpolated tokens to their actual tokens. In that commit
all interpolated tokens were surrounded with a `DelimToken::None` group of
tokens, but this ended up causing regressions like #44730 where the various
attribute parsers in `syntax/attr.rs` weren't ready to cope with
`DelimToken::None`. Instead of fixing the parser in `attr.rs` this commit
instead opts to just avoid the `DelimToken::None` in the first place, ensuring
that the token stream should look the same as it did before where possible.
Closes#44730
Make `-Z borrowck-mir` imply that `EndRegion`'s should be emitted.
Before this change, the `-Z borrowck-mir` flag is useless if you do not also pass `-Z emit-end-regions`.
So, in the same spirit as f2892ad281, make `-Z borrowck-mir` also emit `EndRegion` statements. (This will hopefully avoid some initial speed bumps for new-comers helping out with NLL.)
fix an incorrect assertion in the doc example for `std::io::copy`
I think this wasn't caught by CI because the `foo` wrapper function was only defined and not called. This seems to be the norm for doc examples that define a `foo` function. Is that on purpose?
Expand size_of docs
This PR does 3 things.
1. Adds a description of what pointer size means to the primitive pages for usize and isize.
2. Says the general size of things is not stable from compiler to compiler.
3. Adds a table of sizes of things that we do guarantee. As this is the first table in the libstd docs, I've included a picture of how that looks.
![](https://i.imgur.com/YZ6IChH.png?1)
only set non-ADT derive error once per attribute, not per trait
I found the expansion code very hard to follow, leaving me unsure as to whether this might somehow be done better, but this patch does give us the behavior requested in #43927 (up to exact choice of span; here, it's the entire attribute, not just the `derive` token).
(Note to GitHub robots: _resolves #43927_.)
r? @jseyfried
Although RFC 1940 is about annotating functions with `#[must_use]`, a
key part of the motivation was linting unused equality operators.
(See
https://github.com/rust-lang/rfcs/pull/1812#issuecomment-265695898—it
seems to have not been clear to discussants at the time that marking the
comparison methods as `must_use` would not give us the lints on
comparison operators, at least in (what the present author understood
as) the most straightforward implementation, as landed in #43728
(3645b062).)
To rectify the situation, we here lint unused comparison operators as
part of the unused-must-use lint (feature gated by the `fn_must_use`
feature flag, which now arguably becomes a slight (tolerable in the
opinion of the present author) misnomer).
This is in the matter of #43302.
Add ..= to the parser
Add ..= to libproc_macro
Add ..= to ICH
Highlight ..= in rustdoc
Update impl Debug for RangeInclusive to ..=
Replace `...` to `..=` in range docs
Make the dotdoteq warning point to the ...
Add warning for ... in expressions
Updated more tests to the ..= syntax
Updated even more tests to the ..= syntax
Updated the inclusive_range entry in unstable book
incr.comp.: Move task result fingerprinting into DepGraph.
This PR
- makes the DepGraph store all `Fingerprints` of task results,
- allows `DepNode` to be marked as input nodes,
- makes HIR node hashing use the regular fingerprinting infrastructure,
- removes the now unused `IncrementalHashesMap`, and
- makes sure that `traits_in_scope_map` fingerprints are stable.
r? @nikomatsakis
cc @alexcrichton
Retain suid/sgid/sticky bits in Metadata.permissions
Most users would expect set_permissions(Metadata.permissions()) to be
non-destructive. While we can't guarantee this, we can at least pass
the needed info to chmod.
Also update the PermissionsExt documentation to disambiguate what it
contains, and to refer to the underlying value as `st_mode` rather than
its type `mode_t`.
Closes#44147
Catch IOError in bootstrap.py when loading config.toml
When I pulled this repo and tried to build using the command in the readme, I got an error about a missing `config.toml`.
If config.toml doesn't exist, then an `IOError` will be raised the `with open(...)` line. Prior to e788fa7b6c, this was caught because the `except` clause didn't specify what exceptions it caught, so both `IOError` and `OSError` were caught.
First time contributing, so please let me know if I'm doing anything wrong.
Based on ExpHP's comment in
https://users.rust-lang.org/t/refcell-borrow-mut-get-strange-result/12994
> it would perhaps be nicer if it didn't put something that could be
> misinterpreted as a valid string value
The previous Debug implementation would show:
RefCell { value: "<borrowed>" }
The new one is:
RefCell { value: <borrowed> }
A slight eccentricity of this change is that now non-ADT-derive errors prevent
derive-macro-not-found errors from surfacing (see changes to the
gating-of-derive compile-fail tests).
Resolves#43927.
Add iterator method .rfold(init, function); the reverse of fold
rfold is the reverse version of fold.
Fold allows iterators to implement a different (non-resumable) internal
iteration when it is more efficient than the external iteration implemented
through the next method. (Common examples are VecDeque and .chain()).
Introduce rfold() so that the same customization is available for reverse
iteration. This is achieved by both adding the method, and by having the
Rev\<I> adaptor connect Rev::rfold → I::fold and Rev::fold → I::rfold.
On the surface, rfold(..) is just .rev().fold(..), but the special case
implementations allow a data structure specific fold to be used through for
example .iter().rev(); we thus have gains even for users never calling exactly
rfold themselves.
don't suggest placing `use` statements into expanded code
r? @nrc
fixes#44210
```rust
#[derive(Debug)]
struct Foo;
type X = Path;
```
will try to place `use std::path::Path;` between `#[derive(Debug)]` and `struct Foo;`
I am not sure how to obtain a span before the first attribute, because derive attributes are removed during expansion.
It would be trivial to detect this case and place the `use` after the item, but that would be somewhat weird I think.
If config.toml doesn't exist, then an IOError will be raised
on the `with open(...)` line. Prior to e788fa7, this was
caught because the `except` clause didn't specify what
exceptions it caught, so both IOError and OSError were
caught