Fix for old school error issues, improvements to new school
This PR:
* Fixes some old school error issues, specifically #33559, #33543, #33366
* Improves wording borrowck errors with match patterns
* De-emphasize multi-line spans, so we don't color the single source character when we're trying to say "span starts here"
* Rollup of #33392 (which should help fix#33390)
r? @nikomatsakis
Warnings for issue #32330
This is an extension of the previous PR that issues warnings in more situations than before. It does not handle *all* cases of #32330 but I believe it issues warnings for all cases I've seen in practice.
Before merging I'd like to address:
- open a good issue explaining the problem and how to fix it (I have a [draft writeup][])
- work on the error message, which I think is not as clear as it could/should be (suggestions welcome)
r? @aturon
[draft writeup]: https://gist.github.com/nikomatsakis/631ec8b4af9a18b5d062d9d9b7d3d967
Replace the obligation forest with a graph
In the presence of caching, arbitrary nodes in the obligation forest can be merged, which makes it a general graph. Handle it as such, using cycle-detection algorithms in the processing.
I should do performance measurements sometime.
This was pretty much written as a proof-of-concept. Please help me write this in a less-ugly way. I should also add comments explaining what is going on.
r? @nikomatsakis
add UI testing framework
This adds a framework for capturing and tracking the precise output of rustc, which allows us to check all manner of minor details with the output. It's pretty strict right now -- the output must match almost exactly -- and hence maybe a bit too strict. But I figure we can add wildcards or whatever later. There is also a script intended to make updating the references easy, though the script could make things a *bit* easier (in particular, it'd be nice if it would find the build directory for you automatically).
One thing I was wondering about is the best way to test colors. Since windows doesn't embed those in the output stream, this test framework can't test colors on windows -- so I figure we can just write tests that are ignored on windows and which pass `--color=always` or whatever to rustc.
cc @jonathandturner
r? @alexcrichton
test: explicitely check the number of spawned threads in tcp-stress
System limits may restrict the number of threads effectively spawned by this test (eg. systemd recently introduced a 512 tasks per unit maximum default).
Now this test explicitly asserts on the expected number of threads, making failures due to system limits easier to spot.
More details at https://bugs.debian.org/822325
Remove ExplicitSelf from HIR
`self` argument is already kept in the argument list and can be retrieved from there if necessary, so there's no need for the duplication.
The same changes can be applied to AST, I'll make them in the next breaking batch.
The first commit also improves parsing of method declarations and fixes https://github.com/rust-lang/rust/issues/33413.
r? @eddyb
Batch of improvements to errors for new error format
This is a batch of improvements to existing errors to help get the most out of the new error format.
* Added labels to primary spans (^^^) for a set of errors that didn't currently have them
* Highlight the source blue under the secondary notes for better readability
* Move some of the "Note:" into secondary spans+labels
* Fix span_label to take &mut instead, which makes it work the same as other methods in that set
typeck: if a private field exists, also check for a public method
For example, `Vec::len` is both a field and a method, and usually encountering `vec.len` just means that the parens were forgotten.
Fixes: #26472
NOTE: I added the parameter `allow_private` to `method::exists` since I don't want to suggest inaccessible methods. For the second case, where only the method exists, I think it would make sense to set it to `false` as well, but I wanted to preserve compatibility for this case.
Improve derived implementations for enums with lots of fieldless variants
A number of trait methods like PartialEq::eq or Hash::hash don't
actually need a distinct arm for each variant, because the code within
the arm only depends on the number and types of the fields in the
variants. We can easily exploit this fact to create less and better
code for enums with multiple variants that have no fields at all, the
extreme case being C-like enums.
For nickel.rs and its by now infamous 800 variant enum, this reduces
optimized compile times by 25% and non-optimized compile times by 40%.
Also peak memory usage is down by almost 40% (310MB down to 190MB).
To be fair, most other crates don't benefit nearly as much, because
they don't have as huge enums. The crates in the Rust distribution that
I measured saw basically no change in compile times (I only tried
optimized builds) and only 1-2% reduction in peak memory usage.
System limits may restrict the number of threads effectively spawned
by this test (eg. systemd recently introduced a 512 tasks per unit
maximum default).
This commit explicitly asserts on the expected number of threads,
making failures due to system limits easier to spot.
More details at https://bugs.debian.org/822325
Signed-off-by: Luca Bruno <lucab@debian.org>
Fix spans and expected token lists, fix#33413 + other cosmetic improvements
Add test for #33413
Convert between `Arg` and `ExplicitSelf` precisely
Simplify pretty-printing for methods
trans-collector: Assorted fixes and refactorings needed for making trans collector-driven.
As the title says. The messages on the individual commits should do a good job of explaining what they are about.
r? @nikomatsakis
Don't use env::current_exe with libbacktrace
If the path we give to libbacktrace doesn't actually correspond to the
current process, libbacktrace will segfault *at best*.
cc #21889
r? @alexcrichton
cc @semarie
mir: don't attempt to promote Unpromotable constant temps.
Fixes#33537. This was a non-problem in regular functions, but we also promote in `const fn`s.
There we always qualify temps so you can't depend on `Unpromotable` temps being `NOT_CONST`.
re-introduce a cache for ast-ty-to-ty
It turns out that `ast_ty_to_ty` is supposed to be updating the `def`
after it finishes, but at some point in the past it stopped doing
so. This was never noticed because of the `ast_ty_to_ty_cache`, but that
cache was recently removed. This PR fixes the code to update the def
properly, but apparently that is not quite enough to make the operation
idempotent, so for now we reintroduce the cache too.
Fixes#33586.
r? @eddyb
Make --emit dep-info work correctly with -Z no-analysis again.
Previously, it would attempt to resolve some external crates that weren't necessary for dep-info output.
Fixes#33231.
A number of trait methods like PartialEq::eq or Hash::hash don't
actually need a distinct arm for each variant, because the code within
the arm only depends on the number and types of the fields in the
variants. We can easily exploit this fact to create less and better
code for enums with multiple variants that have no fields at all, the
extreme case being C-like enums.
For nickel.rs and its by now infamous 800 variant enum, this reduces
optimized compile times by 25% and non-optimized compile times by 40%.
Also peak memory usage is down by almost 40% (310MB down to 190MB).
To be fair, most other crates don't benefit nearly as much, because
they don't have as huge enums. The crates in the Rust distribution that
I measured saw basically no change in compile times (I only tried
optimized builds) and only 1-2% reduction in peak memory usage.
It turns out that `ast_ty_to_ty` is supposed to be updating the `def`
after it finishes, but at some point in the past it stopped doing
so. This was never noticed because of the `ast_ty_to_ty_cache`, but that
cache was recently removed. This PR fixes the code to update the def
properly, but apparently that is not quite enough to make the operation
idempotent, so for now we reintroduce the cache too.
Fixes#33425.
const_fn: Check the terminating expression of a block for blocks in a const initializer
In a const or static initializer, the `CheckBlock` check ensures that blocks in the initializer expression are only in tail positions or in items. In this case, it didn't check the terminating expression of a block, which resulted in an ICE later in the compiler pipeline if the trailing expression was itself a block. This change fixes the ICE and ensures that the proper error is emitted. This fixes the ICE in #32829 .
