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
This ICEs in MIR currently, which I think is to be expected since none of the MIR plumbing is set up. I added a test which confirms that the shim is being used for reifying a track_caller function.
Revert "Make `into` schedule drop for the destination"
This was a *very* large perf regression in some cases. I'll undo the revert once I have time to avoid the regression.
