Enable ThinLTO with incremental compilation.
This is an updated version of #52309. This PR allows `rustc` to use (local) ThinLTO and incremental compilation at the same time. In theory this should allow for getting compile-time improvements for small changes while keeping the runtime performance of the generated code roughly the same as when compiling non-incrementally.
The difference to #52309 is that this version also caches the pre-LTO version of LLVM bitcode. This allows for another layer of caching:
1. if the module itself has changed, we have to re-codegen and re-optimize.
2. if the module itself has not changed, but a module it imported from during ThinLTO has, we don't need to re-codegen and don't need to re-run the first optimization phase. Only the second (i.e. ThinLTO-) optimization phase is re-run.
3. if neither the module itself nor any of its imports have changed then we can re-use the final, post-ThinLTO version of the module. (We might have to load its pre-ThinLTO version though so it's available for other modules to import from)
Reduce number of syscalls in `rand`
This skips the initial zero-length `getrandom` call and
directly hands the user buffer to the operating system, saving one
`getrandom` syscall.
Fix of bug introduced by #53762 (tool_lints)
Before implementing backwards compat for tool lints, the `Tool` case when parsing cmdline lints was unreachable. This changed with #53762.
This fix is needed for rls test-pass. (@nrc)
r? @Manishearth
Various small diagnostic and code clean up
- Point at def span on incorrect `panic` or `oom` function
- Use structured suggestion instead of note for `+=` that can be performed on a dereference of the left binding
- Small code formatting cleanup
refactor match guard
This is the first step to implement RFC 2294: if-let-guard. Tracking issue: https://github.com/rust-lang/rust/issues/51114
The second step should be introducing another variant `IfLet` in the Guard enum. I separated them into 2 PRs for the convenience of reviewers.
r? @petrochenkov
Add Error::source method per RFC 2504.
This implements part of RFC 2504.
* Adds `Error::source`, a replacement for `Error::cause` with the "right" signature, which will be instantly stable.
* Deprecates `Error::cause` in 1.33 (this choice was based on the precedent in #52994, which we haven't finalized).
* Redefines `Error::cause` to delegate to `Error::source` (the delegation can only go in this direction, not the other).
@rfcbot fcp merge
set cfg(rustdoc) when rustdoc is running on a crate
When using `#[doc(cfg)]` to document platform-specific items, it's a little cumbersome to get all the platforms' items to appear all at once. For example, the standard library adds `--cfg dox` to rustdoc's command line whenever it builds docs, and the documentation for `#![feature(doc_cfg)]` suggests using a Cargo feature to approximate the same thing. This is a little awkward, because you always need to remember to set `--features dox` whenever you build documentation.
This PR proposes making rustdoc set `#[cfg(rustdoc)]` whenever it runs on a crate, to provide an officially-sanctioned version of this that is set automatically. This way, there's a standardized way to declare that a certain version of an item is specifically when building docs.
To try to prevent the spread of this feature from happening too quickly, this PR also restricts the use of this flag to whenever `#![feature(doc_cfg)]` is active. I'm sure there are other uses for this, but right now i'm tying it to this feature. (If it makes more sense to give this its own feature, i can easily do that.)
Make Arc cloning mechanics clearer in module docs
Add some more wording to module documentation regarding how
`Arc::clone()` works, as some users have assumed cloning Arc's
to work via dereferencing to inner value as follows:
use std::sync::Arc;
let myarc = Arc::new(1);
let myarcref = myarc.clone();
assert!(1 == myarcref);
Instead of the actual mechanic of referencing the existing
Arc value:
use std::sync::Arg;
let myarc = Arc::new(1);
let myarcref = myarc.clone();
assert!(myarcref == &myarc); // not sure if assert could assert this in the real world
bench: libcore: fix build failure of any.rs benchmark (use "dyn Any")
fixes
````
error: trait objects without an explicit `dyn` are deprecated
--> libcore/../libcore/benches/any.rs:18:36
|
18 | let mut y = &mut x as &mut Any;
| ^^^ help: use `dyn`: `dyn Any`
|
= note: requested on the command line with `-D bare-trait-objects`
````
Add rust-gdbgui script.
This script invokes the [gdbgui](https://gdbgui.com/) graphical GDB front-end with the Rust pretty printers loaded. The script does not install gdbgui, that must be done manually.
As an escapee from Visual Studio it is nice to have a point-and-click debugger. This script invokes `gdbgui` similarly to the way that `rust-gdb` invokes `gdb` - I copied that script as a starting point.
Because it is a wrapper around a wrapper you don't have as much flexibility in passing arguments to GDB and I could not find a way to eliminate the single quotes you have to use when you want to pass arguments to your program (`gdbgui` supposedly supports an `--args` option which I think should allow this, but I couldn't get it to work, my shell-fu is weak). Still, I find this very usable for debugging programs, and it is a lot more approachable than gdb in the terminal.
Implement the `min_const_fn` feature gate
cc @RalfJung @eddyb
r? @Centril
implements the feature gate for #53555
I added a hack so the `const_fn` feature gate also enables the `min_const_fn` feature gate. This ensures that nightly users of `const_fn` don't have to touch their code at all.
The `min_const_fn` checks are run first, and if they succeeded, the `const_fn` checks are run additionally to ensure we didn't miss anything.
Backwards compatibility for tool/clippy lints
cc #44690
cc https://github.com/rust-lang-nursery/rust-clippy/pull/2977#issuecomment-409706557
This is the next step towards `tool_lints`.
This makes Clippy lints still work without scoping, but will warn and suggest the new scoped name. This warning will only appear if the code is checked with Clippy itself.
There is still an issue with using the old lint name in inner attributes. For inner attributes the warning gets emitted twice. I'm currently not really sure why this happens, but will try to fix this ASAP.
r? @Manishearth
Update LLVM submodule
This commit updates the LLVM submodule to the current trunk of LLVM itself. This
brings a few notable improvements for the wasm target:
* Support for wasm atomic instructions is greatly improved
* Renamed memory wasm intrinsics are fully supported
* LLD has fixed a quadratic execution bug with large numbers of relocations in
wasm files.
The compiler-rt submodule has been updated in tandem as well.
