Mark Path::join as must_use
I've accidentally did `mut_path_buf.jon(a_path);`, expecting this to be an in-place modification. Seems like we can easily warn in such cases?
Deduplicate is_{freeze,copy,sized}_raw
Fixes#65259
Deduplicates `is_{freeze,copy,sized}_raw` by delegating to a new method which takes in a `LangItem`.
Update LLVM for Emscripten exception handling support
Updates LLVM to pick up the cherry-picked support for correctly
handling exception handling with aggregates passed by value. This will
be necessary to continue to support Emscripten's exception handling
once we switch using Emscripten's LLVM backend. See #63649.
Add ?Sized bound to a supertrait listing in E0038 error documentation
This example failed to compile because of implicit `Sized` bound for `A` parameter that wasn't required by `Trait`.
Add some regression tests
- Add a test for #62187.
- Clean up the directory structure in `src/test/ui/const-generics`
- Closes#64792.
- Closes#57399.
- Closes#57271.
Added doc about behavior of extend on HashMap
It was unclear what the implementation does when it encounters existing keys. This change makes it clear by documenting the trait impl.
Research suggests that we are not properly testing this case anyway, and
even if we were, it is unlikely that we will regress here -- or, perhaps
more accurately, if we do, I am uncertain that we care too much. It
definitely seems like an edge case, and one that is particularly
unlikely to occur as time goes on.
The dummy Span pointed to the beginning of the source file instead to
where the `#[derive]` is located. Later, it tripped the
`in_derive_expansion(span)` check at `src/librustc/middle/stability.rs`,
causing a span-less deprecation warning to be emitted.
Fixes#56195, #55417.
minimize the rust-std component
This changes the `rust-std` dist component to only include the artifacts of compiling the `libstd` step, as listed in `.libstd.stamp`. This does include `test` and `proc-macro` as well. The remaining _unstable_ libraries that are built as part of `rustc` are packaged into a new `rustc-dev` component, intended for use in the development of closely related tools (clippy, miri, rls).
Here are the component sizes from the [try build](https://dev-static.rust-lang.org/dist/2019-10-07/index.html):
| Name | Size
| --- | ---
| rust-std-nightly-x86_64-unknown-linux-gnu.tar.gz | 23.94 MiB
| rust-std-nightly-x86_64-unknown-linux-gnu.tar.xz | 17.4 MiB
| rustc-dev-nightly-x86_64-unknown-linux-gnu.tar.gz | 182.03 MiB
| rustc-dev-nightly-x86_64-unknown-linux-gnu.tar.xz | 157.91 MiB
Fixes#61978Fixes#62486
Improve message when attempting to instantiate tuple structs with private fields
Fixes#58017, fixes#39703.
```
error[E0603]: tuple struct `Error` is private
--> main.rs:22:16
|
2 | pub struct Error(usize, pub usize, usize);
| ----- ----- field is private
| |
| field is private
...
22 | let x = a::Error(3, 1, 2);
| ^^^^^
|
= note: a tuple struct constructor is private if any of its fields is private
```
Add llvm.sideeffect to potential infinite loops and recursions
LLVM assumes that a thread will eventually cause side effect. This is
not true in Rust if a loop or recursion does nothing in its body,
causing undefined behavior even in common cases like `loop {}`.
Inserting llvm.sideeffect fixes the undefined behavior.
As a micro-optimization, only insert llvm.sideeffect when jumping back
in blocks or calling a function.
A patch for LLVM is expected to allow empty non-terminate code by
default and fix this issue from LLVM side.
https://github.com/rust-lang/rust/issues/28728
**UPDATE:** [Mentoring instructions here](https://github.com/rust-lang/rust/pull/59546#issuecomment-515072429) to unstall this PR
