Rollup of 8 pull requests
Successful merges:
- #52453 (improve diagnostics for tests with custom return values)
- #53271 (use ? to simplify `TransitiveRelation.maybe_map`)
- #53279 (Extend documentation of `rustc_on_unimplemented`)
- #53342 (fix error for unsized packed struct field)
- #53344 (Add doc examples for std::alloc::{alloc,alloc_zeroed}.)
- #53368 (Ignore test that fails on stage1)
- #53388 (Fix links' color)
- #53396 (Fix since of Iterator::flatten to be a proper semver)
Failed merges:
r? @ghost
fix error for unsized packed struct field
It was really confusing to be told "only the last field of a struct may have a dynamically sized type" when only the last field *was* unsized.
improve diagnostics for tests with custom return values
This is an attempt at getting the ball rolling to improve the diagnostics for test functions that return custom `impl Termination` values (see #52436).
An alternative could be to use `eprintln!`, but including this in the panic message felt nicely consistent with how failing test assertions would be reported.
Let me know what you think!
In `librustc_apfloat/ieee.rs`, use the iterator.[r]find methods to
simplify the code. In `libserialize/json.rs`, make use of the fact
that `Vec.last` on an empty `Vec` returns `None` to simplify the
code to a single match.
The former code used `target.contains("64")` to detect Elf64 targets,
but this is inaccurate in a few cases:
- `s390x-unknown-linux-gnu` is 64-bit
- `sparcv9-sun-solaris` is 64-bit
- `x86_64-unknown-linux-gnux32` is 32-bit
Instead the `std` build script can use `CARGO_CFG_TARGET_POINTER_WIDTH`
to reliably detect 64-bit targets for libbacktrace.
Also update to backtrace-sys 0.1.24 for alexcrichton/backtrace-rs#122.
Add lldb to the build
This optionally adds lldb (and clang, which it needs) to the build.
Because rust uses LLVM 7, and because clang 7 is not yet released, a
recent git master version of clang is used.
The lldb that is used includes the Rust plugin.
lldb is only built when asked for, or when doing a nightly build on
macOS. Only macOS is done for now due to difficulties with the Python
dependency.
This optionally adds lldb (and clang, which it needs) to the build.
Because rust uses LLVM 7, and because clang 7 is not yet released, a
recent git master version of clang is used.
The lldb that is used includes the Rust plugin.
lldb is only built when asked for, or when doing a nightly build on
macOS. Only macOS is done for now due to difficulties with the Python
dependency.
(old) borrowck cleanup
Primarily moves dataflow code based on CFG to borrowck; this is mostly so we don't forget to delete it once it becomes unused after we fully move to MIR borrowck.