Further tweak lifetime errors involving `dyn Trait` and `impl Trait` in return position
* Suggest substituting `'static` lifetime in impl/dyn `Trait + 'static` instead of `Trait + 'static + '_`
* When `'static` is explicit, also suggest constraining argument with it
* Reduce verbosity of suggestion message and mention lifetime in label
* Tweak output for overlapping required/captured spans
* Give these errors an error code
Follow up to #72543.
r? @nikomatsakis
Add tests for 'impl Default for [T; N]'
Related: #71690.
This pull request adds two tests:
- Even it T::default() panics, no leaks occur.
- [T; 0] is Default even if T is not.
I believe at some moment `Default` impl for arrays will be rewritten to use const generics instead of macros, and these tests will help to prevent behavior changes.
add raw_ref macros
In https://github.com/rust-lang/rust/issues/64490, various people were in favor of exposing `&raw` as a macro first before making the actual syntax stable. So this PR (unstably) introduces those macros.
I'll create the tracking issue if we're okay moving forward with this.
Improve diagnostics for `let x += 1`
Fixes(?) #66736
The code responsible for the `E0404` errors is [here](https://github.com/rust-lang/rust/blob/master/src/librustc_parse/parser/ty.rs#L399-L424) which I don't think can be easily modified to prevent emitting an error in one specific case. Because of this I couldn't get rid of `E0404` and instead added `E0067` along with a help message which will fix the problem.
r? @estebank
[RISC-V] Do not force frame pointers
We have been seeing some very inefficient code that went away when using
`-Cforce-frame-pointers=no`. For instance `core::ptr::drop_in_place` at
`-Oz` was compiled into a function which consisted entirely of saving
registers to the stack, then using the frame pointer to restore the same
registers (without any instructions between the prolog and epilog).
The RISC-V LLVM backend supports frame pointer elimination, so it makes
sense to allow this to happen when using Rust. It's not clear to me that
frame pointers have ever been required in the general case.
In rust-lang/rust#61675 it was pointed out that this made reassembling
stack traces easier, which is true, but there is a code generation
option for forcing frame pointers, and I feel the default should not be
to require frame pointers, given it demonstrably makes code size worse
(around 10% in some embedded applications).
The kinds of targets mentioned in rust-lang/rust#61675 are popular, but
should not dictate that code generation should be worse for all RISC-V
targets, especially as there is a way to use CFI information to
reconstruct the stack when the frame pointer is eliminated. It is also
a misconception that `fp` is always used for the frame pointer. `fp` is
an ABI name for `x8` (aka `s0`), and if no frame pointer is required,
`x8` may be used for other callee-saved values.
---
I am partly posting this to get feedback from @fintelia who introduced the change to require frame pointers, and @hanna-kruppe who had issues with the original PR. I would understand if we wanted to remove this setting on only a subset of RISC-V targets, but my preference would be to remove this setting everywhere.
There are more details on the code size savings seen in Tock here: https://github.com/tock/tock/pull/1660
Update LLVM submodule
Only includes one commit:
- [D80759](https://reviews.llvm.org/D80759): Fix FastISel dropping srcloc metadata from InlineAsm
Fixes#40555
Rollup of 8 pull requests
Successful merges:
- #73237 (Check for overflow in DroplessArena and align returned memory)
- #73339 (Don't run generator transform when there's a TyErr)
- #73372 (Re-order correctly the sections in the sidebar)
- #73373 (Use track caller for bug! macro)
- #73380 (Add more info to `x.py build --help` on default value for `-j JOBS`.)
- #73381 (Fix typo in docs of std::mem)
- #73389 (Use `Ipv4Addr::from<[u8; 4]>` when possible)
- #73400 (Fix forge-platform-support URL)
Failed merges:
r? @ghost
Re-order correctly the sections in the sidebar
Before that, "trait implementations" and "implementors" titles in the sidebar were before "methods" for example. Which wasn't logical considering that the two sections come after in the "content".
r? @kinnison
Don't run generator transform when there's a TyErr
Not sure if this might cause any problems later on, but we shouldn't be hitting codegen or const eval for the produced MIR anyways, so it should be fine.
cc https://github.com/rust-lang/rust/issues/72685#issuecomment-643749020
Check for overflow in DroplessArena and align returned memory
* Check for overflow when calculating the slice start & end position.
* Align the pointer obtained from the allocator, ensuring that it
satisfies user requested alignment (the allocator is only asked for
layout compatible with u8 slice).
* Remove an incorrect assertion from DroplessArena::align.
* Avoid forming references to an uninitialized memory in DroplessArena.
Helps with #73007, #72624.
Avoid prematurely recording toolstates
When we're running with dry_run enabled (i.e. all builds do this initially), we're
guaranteed to save of a toolstate of TestFail for tools that aren't tested. In practice,
we do test tools as well, so for those tools we would initially record them as being
TestPass, and then later on re-record the correct state after actually testing them.
However, this would not work well if the build failed for whatever reason (e.g. panicking
in bootstrap, or as was the case in #73097, clippy failing to test successfully), we would
just go on believing that things passed when they in practice did not.
This commit also adjusts saving toolstate to never record clippy explicitly (otherwise, it
would be recorded when building it); eventually that'll likely move to other tools as well
but not yet. This is deemed simpler than checking everywhere we generically save
toolstate.
We also move clippy out of the "toolstate" no-fail-fast build into a separate x.py
invocation; this should no longer be technically required but provides the nice state of
letting us check toolstate for all tools and only then check clippy (giving full results
on every build).
r? @oli-obk
Supercedes #73275, also fixes#73274
store `ObligationCause` on the heap
Stores `ObligationCause` on the heap using an `Rc`.
This PR trades off some transient memory allocations to reduce the size of–and thus the number of instructions required to memcpy–a few widely used data structures in trait solving.
When we're running with dry_run enabled (i.e. all builds do this initially), we're
guaranteed to save of a toolstate of TestFail for tools that aren't tested. In practice,
we do test tools as well, so for those tools we would initially record them as being
TestPass, and then later on re-record the correct state after actually testing them.
However, this would not work well if the build failed for whatever reason (e.g. panicking
in bootstrap, or as was the case in 73097, clippy failing to test successfully), we would
just go on believing that things passed when they in practice did not.
This commit also adjusts saving toolstate to never record clippy explicitly (otherwise, it
would be recorded when building it); eventually that'll likely move to other tools as well
but not yet. This is deemed simpler than checking everywhere we generically save
toolstate.
We also move clippy out of the "toolstate" no-fail-fast build into a separate x.py
invocation; this should no longer be technically required but provides the nice state of
letting us check toolstate for all tools and only then check clippy (giving full results
on every build).
Implement new gdb/lldb pretty-printers
Reopened#60826
This PR replaces current gdb and lldb pretty-printers with new ones that were originally written for [IntelliJ Rust](https://github.com/intellij-rust/intellij-rust/tree/master/prettyPrinters).
The current state of lldb pretty-printers is poor, because [they don't use synthetic children](https://github.com/rust-lang/rust/issues/55586#issuecomment-436610063). When I started to reimplement lldb pretty-printers with synthetic children support, I've found current version strange and hard to support. I think `debugger_pretty_printers_common.py` is overkill, so I got rid of it.
The new pretty-printers have to support all types supported by current pretty-printers, and also support `Rc`, `Arc`, `Cell`, `Ref`, `RefCell`, `RefMut`, `HashMap`, `HashSet`.
Fixes#56252
Manish Goregaokar
bors
Who? Me?!
Dylan DPC
Raphael Nestler
Ralf Jung
Lzu Tao
mark
Vadim Petrochenkov
ivan tkachenko
Esteban Küber
Felix S. Klock II
Mark Rousskov
Guillaume Gomez