lint: deny incoherent_fundamental_impls by default
Warn the ecosystem of the pending intent-to-disallow in #49799.
There are 4 ICEs on my machine, look unrelated (having happened before in https://github.com/rust-lang/rust/issues/49146#issuecomment-384473523)
```rust
thread 'main' panicked at 'assertion failed: position <= slice.len()', libserialize/leb128.rs:97:1
```
```
[run-pass] run-pass/allocator/xcrate-use2.rs
[run-pass] run-pass/issue-12133-3.rs
[run-pass] run-pass/issue-32518.rs
[run-pass] run-pass/trait-default-method-xc-2.rs
```
r? @nikomatsakis
This splits into_slices() into into_key_slice() and into_val_slice(). While the
extra calls would get optimized out, this is a useful semantic change since we
call keys() while iterating, and we don't want to construct and out-of-bounds
val() pointer in the process if we happen to be pointing to the shared static
root.
This also paves the way for doing the alignment handling conditional differently
for the keys and values.
This gives a pointer to that static empty node instead of allocating
a new node, and then whenever inserting makes sure that the root
isn't that empty node.
This way we can safely statically allocate a LeafNode to use as the
placeholder before allocating, and any type accessing it will be able to
access the metadata at the same offset.
idiom lints for removing `extern crate`
Based off of https://github.com/rust-lang/rust/pull/49789
This contains two lints:
- One that suggests replacing pub extern crates with pub use, and removing non-pub extern crates entirely
- One that suggests rewriting `use modulename::...::cratename::foo` as `cratename::foo`
The latter is a bit tricky to emit suggestions for; for one this involves splicing spans (never a good idea), and it also won't be able to correctly
handle `use module::{cratename, foo}` and use-trees. I'm not sure how to proceed here. Currently it doesn't suggest anything at all.
Perhaps we can go the other way and suggest removal of all extern crates _except_ those used through modules (stash node ids somewhere) and suggest replacing those with `<visibility> use`?
r? @nikomatsakis
fixes https://github.com/rust-lang/rust/issues/48719
trim and pass relative test paths as test-args
use collect for getting test_args
move suite_path to ShouldRun and make Option
append existing args to test_args
use enum for PathSet
handle Suites differently from Paths
Error out if part of test suite but not file
refactor, make requested changes
Use ManuallyDrop instead of Option in BinaryHeap Hole implementation
The Option is always Some until drop, where it becomes None. Make this more explicit and avoid unwraps by using ManuallyDrop.
This change should be performance-neutral as LLVM already optimizes the unwraps away in the inlined code. However I've seen this pattern copied from here to other crates where it is not optimized away, so I think it would be good to change it.
Add some groundwork for cross-language LTO.
Implements part of #49879:
- Adds a `-Z cross-lang-lto` flag to rustc
- Makes sure that bitcode is embedded in object files if the flag is set.
This should already allow for using cross language LTO for staticlibs (where one has to invoke the linker manually anyway). However, `rustc` will not try to enable LTO for its own linker invocations yet.
r? @alexcrichton
Pass a test directory to rustfmt
Another attempt to fix the rustfmt tests. `RUSTFMT_TEST_DIR` is consumed by Rustfmt in the latext commit (thus the Rustfmt update) because we need a place to create temp files that won't be read-only.
r? @alexcrichton
Issue 49938: Reference tagged unions discr(iminant) as tag
Here the changes reference the Tagged type _discriminant_ as _tag_ instead. This is the correct terminology when referencing how tagged unions are represented in memory.
Fix ICE in assertion macro
Fixes#50471. Needs beta-backport (stable-to-beta/nightly regression).
* `panic` with single argument does not need escaping `{` and `}`
* Instead of unescaping `\u{...}` manually, just use `escape_debug` in pprust
The Option is always Some until drop, where it becomes None. Make
this more explicit and avoid unwraps by using ManuallyDrop.
This change should be performance-neutral as LLVM already optimizes
the unwraps away in the inlined code.
rustbuild: Allow quick testing of libstd and libcore at stage0
This PR implemented two features:
1. Added a `--no-doc` flag to allow testing a crate *without* doc tests. In this mode, we don't need to build rustdoc, and thus we can skip building the stage2 compiler. (Ideally stage0 test should use the bootstrap rustdoc, but I don't want to mess up the core builder logic here)
2. Moved all libcore tests externally and added a tidy test to ensure we don't accidentally add `#[test]` into libcore.
After this PR, one could run `./x.py test --stage 0 --no-doc src/libstd` to test `libstd` without building the compiler, thus enables us to quickly test new library features.
proc_macro: Explicitly make everything !Send/Sync
This commit adds explicit imp blocks to ensure that all publicly exported types
(except simple enums) are not `Send` nor `Sync` in the `proc_macro` crate.
cc #38356
Refer https://github.com/rust-lang/rust/issues/49938
Previously tagged unions' tag was refered to as a discr(iminant).
Here the changes use tag instead which is the correct terminology
when refering to the memory representation of tagged unions.
