Simplify librustc_errors
This is part 2 of the error crate refactor, starting with #34403.
In this refactor, I focused on slimming down the error crate to fewer moving parts. As such, I've removed quite a few parts and replaced the with simpler, straight-line code. Specifically, this PR:
* Removes BasicEmitter
* Remove emit from emitter, leaving emit_struct
* Renames emit_struct to emit
* Removes CoreEmitter and focuses on a single Emitter
* Implements the latest changes to error format RFC (#1644)
* Removes (now-unused) code in emitter.rs and snippet.rs
* Moves more tests to the UI tester, removing some duplicate tests in the process
There is probably more that could be done with some additional refactoring, but this felt like it was getting to a good state.
r? @alexcrichton cc: @Manishearth (as there may be breaking changes in stuff I removed/changed)
llvm, rt: build using the Ninja generator if available
The Ninja generator generally builds much faster than make. It may also
be used on Windows to have a vast speed improvement over the Visual
Studio generators.
Currently hidden behind an `--enable-ninja` flag because it does not
obey the top-level `-j` or `-l` flags given to `make`.
Fix up documentation around no_std
1. Fix the sections in the book to have the correct signatures. I've
also marked them as `ignore`; there's no way to set the `no_std`
feature for libc, so it pulls in the stdlib, so this wasn't even
testing the actual thing it was testing. Better to just ignore.
2. Correcting libcore's docs for factual inaccuracy, and add a note
about language items.
Fixes#33677
r? @alexcrichton
If local-rust is the same as the current version, then force a local-rebuild
In Debian, we would like the option to build/rebuild the current release from
*either* the current or previous stable release. So we use enable-local-rust
instead of enable-local-rebuild, and read the bootstrap key dynamically from
whatever is installed locally.
In general, it does not make much sense to allow enable-local-rust without also
setting the bootstrap key, since the build would fail otherwise.
(The way I detect "the bootstrap key of [the local] rustc installation" is a bit hacky, suggestions welcome.)
Better error message for inner attribute following doc comment
Before it was always just "an inner attribute is not permitted in this context", whereas now we add a special case for when an inner attr follows an outer attr. If the outer attr is a doc comment, then the error is "an inner attr is not permitted following a doc comment", and otherwise it's "an inner attr is not permitted following an outer attribute". In all other cases it's still "an inner attribute is not permitted in this context".
Note that the public API and behaviour of `parse_attribute` is unchanged. Also, all new names are very open to bikeshedding -- they're arguably clunky.
Fixes#34516. cc @brson
mk: Don't pass -msoft-float on mips-gnu
Soon the LLVM upgrade (#34743) will require an updated CMake installation, and
the easiest way to do this was to upgrade the Ubuntu version of the bots to
16.04. This in turn brings in a new MIPS compiler on the linux-cross builder,
which is now from the "official" ubuntu repositories. Unfortunately these
new compilers don't support compiling with the `-msoft-float` flag like we're
currently passing, causing compiles to fail.
This commit removes these flags as it's not clear *why* they're being passed, as
the mipsel targets also don't have it. At least if it's not supported by a
debian default compiler, perhaps it's not too relevant to support?
Soon the LLVM upgrade (#34743) will require an updated CMake installation, and
the easiest way to do this was to upgrade the Ubuntu version of the bots to
16.04. This in turn brings in a new MIPS compiler on the linux-cross builder,
which is now from the "official" ubuntu repositories. Unfortunately these
new compilers don't support compiling with the `-msoft-float` flag like we're
currently passing, causing compiles to fail.
This commit removes these flags as it's not clear *why* they're being passed, as
the mipsel targets also don't have it. At least if it's not supported by a
debian default compiler, perhaps it's not too relevant to support?
1. Fix the sections in the book to have the correct signatures. I've
also marked them as `ignore`; there's no way to set the `no_std`
feature for libc, so it pulls in the stdlib, so this wasn't even
testing the actual thing it was testing. Better to just ignore.
2. Correcting libcore's docs for factual inaccuracy, and add a note
about language items.
Fixes#33677
Simplify the macro hygiene algorithm
This PR removes renaming from the hygiene algorithm and treats differently marked identifiers as unequal.
This change makes the scope of identifiers in `macro_rules!` items empty. That is, identifiers in `macro_rules!` definitions do not inherit any semantics from the `macro_rules!`'s scope.
Since `macro_rules!` macros are items, the scope of their identifiers "should" be the same as that of other items; in particular, the scope should contain only items. Since all items are unhygienic today, this would mean the scope should be empty.
However, the scope of an identifier in a `macro_rules!` statement today is the scope that the identifier would have if it replaced the `macro_rules!` (excluding anything unhygienic, i.e. locals only).
To continue to support this, this PR tracks the scope of each `macro_rules!` and uses it in `resolve` to ensure that an identifier expanded from a `macro_rules!` gets a chance to resolve to the locals in the `macro_rules!`'s scope.
This PR is a pure refactoring. After this PR,
- `syntax::ext::expand` is much simpler.
- We can expand macros in any order without causing problems for hygiene (needed for macro modularization).
- We can deprecate or remove today's `macro_rules!` scope easily.
- Expansion performance improves by 25%, post-expansion memory usage decreases by ~5%.
- Expanding a block is no longer quadratic in the number of `let` statements (fixes#10607).
r? @nrc
doc: ffi referenced rust-snappy can not compile
r? @steveklabnik
The referenced code https://github.com/thestinger/rust-snappy can not work. Maybe it's the old rust version? I do not know.
So I try to rewrite these test cases. If it is not what you originally meaning, just ignored it.
doc: Mention that writeln! and println! always use LF
Fixes#34697
I'm not really satisfied with the wording, but I didn't have a better idea. Suggestions welcome.
Improve arc doc, fixing #32905
As issue #32905 detailed, I moved part of the module doc to the struct doc, and fixed some small places in the `alloc::arc`.
rustbuild: doc fixes
This fixes two issues rustbuild currently has when building documentation:
1. It fixes standalone builds of `doc-test` and `doc-rustc`.
2. It actually builds the compiler docs if requested in the config.
Closes#34275.
