Fixes#80336
Due to macro expansion, we may end up with spans with an invalid
location and non-root `SyntaxContext`. This commits preserves the
`SyntaxContext` of such spans in the incremental cache, and ensures
that we always hash the `SyntaxContext` when computing the `Fingerprint`
of a `Span`
Previously, we would discard the `SyntaxContext` during serialization to
the incremental cache, causing the span's `Fingerprint` to change across
compilation sessions.
Consistently avoid constructing optimized MIR when not doing codegen
The optimized MIR for closures is being encoded unconditionally, while
being unnecessary for cargo check. This turns out to be especially
costly with MIR inlining enabled, since it triggers computation of
optimized MIR for all callees that are being examined for inlining
purposes https://github.com/rust-lang/rust/pull/77307#issuecomment-751915450.
Skip encoding of optimized MIR for closures, enum constructors, struct
constructors, and trait fns when not doing codegen, like it is already
done for other items since 49433.
Add allow-by-default lint on implicit ABI in extern function pointers and items
This adds a new lint, missing_abi, which lints on omitted ABIs on extern blocks, function declarations, and function pointers.
It is currently not emitting the best possible diagnostics -- we need to track the span of "extern" at least or do some heuristic searching based on the available spans -- but seems good enough for an initial pass than can be expanded in future PRs.
This is a pretty large PR, but mostly due to updating a large number of tests to include ABIs; I can split that into a separate PR if it would be helpful, but test updates are already in dedicated commits.
This is not particularly pretty but the current situation is a mess
and I don't think I'm making it significantly worse.
Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk>
As discussed in #79982.
I think the "new interfaces", ie the new trait and impl, must be
insta-stable. This seems OK because we are, in fact, adding a new
restriction to the stable API.
Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk>
We need to be clear that this never returns WSTOPSIG. That is, if
WIFSTOPPED, the return value is None.
Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk>
A unix wait status can contain, at least, exit statuses, termination
signals, and stop signals.
WTERMSIG is only valid if WIFSIGNALED.
https://pubs.opengroup.org/onlinepubs/9699919799/functions/wait.html
It will not be easy to experience this bug with `Command`, because
that doesn't pass WUNTRACED. But you could make an ExitStatus
containing, say, a WIFSTOPPED, from a call to one of the libc wait
functions.
(In the WIFSTOPPED case, there is WSTOPSIG. But a stop signal is
encoded differently to a termination signal, so WTERMSIG and WSTOPSIG
are by no means the same.)
Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk>
Try to avoid locals when cloning into Box/Rc/Arc
For generic `T: Clone`, we can allocate an uninitialized box beforehand,
which gives the optimizer a chance to create the clone directly in the
heap. For `T: Copy`, we can go further and do a simple memory copy,
regardless of optimization level.
The same applies to `Rc`/`Arc::make_mut` when they must clone the data.
Stabilize split_inclusive
### Contents of this MR
This stabilises:
* `slice::split_inclusive`
* `slice::split_inclusive_mut`
* `str::split_inclusive`
Closes#72360.
### A possible concern
The proliferation of `split_*` methods is not particularly pretty. The existence of `split_inclusive` seems to invite the addition of `rsplit_inclusive`, `splitn_inclusive`, etc. We could instead have a more general API, along these kinds of lines maybe:
```
pub fn split_generic('a,P,H>(&'a self, pat: P, how: H) -> ...
where P: Pattern
where H: SplitHow;
pub fn split_generic_mut('a,P,H>(&'a mut self, pat: P, how: H) -> ...
where P: Pattern
where H: SplitHow;
trait SplitHow {
fn reverse(&self) -> bool;
fn inclusive -> bool;
fn limit(&self) -> Option<usize>;
}
pub struct SplitFwd;
...
pub struct SplitRevInclN(pub usize);
```
But maybe that is worse.
### Let us defer that? ###
This seems like a can of worms. I think we can defer opening it now; if and when we have something more general, these two methods can become convenience aliases. But I thought I would mention it so the lang API team can consider it and have an opinion.
The ICE message is somewhat confusing and overly specific - the issue is
that there's no MIR available.
This should make debugging these ICEs easier since the error tells you
what's actually wrong, not what it was trying to do when it failed.
cc https://github.com/rust-lang/rust/pull/80952#issuecomment-759198841
For example, this code:
struct S(i32, f32);
let S(x) = S(0, 1.0);
will make the compiler suggest either:
let S(x, _) = S(0, 1.0);
or:
let S(x, ..) = S(0, 1.0);
Fix rustdoc --test-builder argument parsing
My suggested fix to issue #80893. I can actually hook Miri in there now.
I also fixed what I believe to be a typo in the option's help text.
