The reverse conversion unfortunately causes unexpected errors like:
```
error[E0277]: the trait bound `!: std::convert::From<()>` is not satisfied
--> src/librustc_metadata/encoder.rs:105:9
|
105 | self.emit_usize(seq.len)?;
| ^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `std::convert::From<()>` is not implemented for `!`
|
= help: the following implementations were found:
<! as std::convert::From<std::convert::Infallible>>
= note: the trait is implemented for `()`. Possibly this error has been caused by changes to Rust's type-inference algorithm (see: https://github.com/rust-lang/rust/issues/48950 for more info). Consider whether you meant to use the type `()` here instead.
= note: required by `std::convert::From::from`
```
I don’t understand why this error happens.
If I’m reading the code correctly the return types of `emit_usize`
and of the method that contains line 105 are both `Result<(), !>`,
so the expansion of the `?` operator should involve `!: From<!>`,
not `From<()>`.
Is this a type inference bug?
Fixes rustdoc in stage 0, stage 1
When a request for rustdoc is passed for stage 0, x.py build --stage 0
src/tools/rustdoc or ensure(tool::Rustdoc { .. }) with top_stage = 0, we
return the rustdoc for that compiler (i.e., the beta rustdoc).
This fixes stage 0 of https://github.com/rust-lang/rust/issues/52186 as well as being part of general workflow improvements (making stage 0 testing for std work) for rustbuild.
The stage 1 fix (second commit) completely resolves the problem, so this fixes https://github.com/rust-lang/rust/issues/52186.
SGX target: simplify usercall internals
This moves logic from assembly to Rust and removes the special case for exit/panic handling, merging it with regular usercall handling.
Also, this fixes a bug in the exit usercall introduced in a75ae00. The bug would make regular exits look like panics with high probability. It would also with some probability leak information through uncleared registers.
cc @VardhanThigle
r? @alexcrichton
use Ubuntu keyserver for CloudABI ports
The Ubuntu keyserver is more reliable than the MIT PGP server, which is
prone to going down. This commit also explicitly uses port 80 on the
keyserver for reasons outlined in #57844.
Rename rustc_errors dependency in rust 2018 crates
I think this is a better solution than `use rustc_errors as errors` in `lib.rs` and `use crate::errors` in modules.
Related: rust-lang/cargo#5653
cc #58099
r? @Centril
fix str mutating through a ptr derived from &self
Found by Miri: In `get_unchecked_mut` (also used by the checked variants internally) uses `str::as_ptr` to create a mutable reference, but `as_ptr` takes `&self`. This means the mutable references we return here got created from a shared reference, which violates the shared-references-are-read-only discipline!
For this by using a newly introduced `as_mut_ptr` instead.
Cleanup: rename node_id_to_type(_opt)
Renames `node_id_to_type(_opt)` to `hir_id_to_type(_opt)`; this makes it clear we are dealing with HIR nodes and their IDs here.
In addition, a drive-by commit removing `ty::item_path::hir_path_str` (as requested by @eddyb).
Speed up the fast path for assert_eq! and assert_ne!
Currently, the panic!() calls directly borrow the value bindings. This
causes those bindings to always be initialized, i.e. they're initialized
even before the values are even compared. This causes noticeable
overhead in what should be a really cheap operation.
By performing a reborrow of the value in the call to panic!(), we allow
LLVM to optimize that code, so that the extra borrow only happens in the
error case.
We could achieve the same result by dereferencing the values passed to
panic!(), as the format machinery borrows them anyway, but this causes
assertions to fail to compile if one of the values is unsized, i.e. it
would be a breaking change.
Cosmetic improvements to doc comments
This has been factored out from https://github.com/rust-lang/rust/pull/58036 to only include changes to documentation comments (throughout the rustc codebase).
r? @steveklabnik
Once you're happy with this, maybe we could get it through with r=1, so it doesn't constantly get invalidated? (I'm not sure this will be an issue, but just in case...) Anyway, thanks for your advice so far!
The Ubuntu keyserver is more reliable than the MIT PGP server, which is
prone to going down. This commit also explicitly uses port 80 on the
keyserver for reasons outlined in #57844.
Require a list of features in `#[allow_internal_unstable]`
The blanket-permission slip is not great and will likely give us trouble some point down the road.
use ignore directives for run-make tests
This makes the tests easier to read, and makes it possible to tell which
tests aren't being run on the host platform.
Fixes#56704.
