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
Some places use the local `tcx` variable, some use `self.tcx()`. This
commit removes the local variable so that all places use `self.tcx()`,
for consistency.
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.
