Fix ICE in `unnecessary_to_owned`
Fixes#9504
Compiler generated call `into_future` nodes return empty substs which we need when checking it's predicates. Handle this by simply exitting when we encounter one. This change introduces false negatives in place of the ICEs.
changelog: [`unnecessary_to_owned`]: fix ICE
Fixes#9504
Compiler generated call `into_iter` nodes return empty substs
which we need when checking it's predicates. Handle this by
simply exitting when we encounter one. This change introduces
false negatives in place of the ICEs.
a fn pointer doesn't implement `Fn`/`FnMut`/`FnOnce` if its return type isn't sized
I stumbled upon #83915 which hasn't received much attention recently, and I wanted to revive it since this is one existing soundness hole that seems pretty easy to fix.
I'm not actually sure that the [alternative approach described here](https://github.com/rust-lang/rust/pull/83915#issuecomment-823643322) is sufficient, given the `src/test/ui/function-pointer/unsized-ret.rs` example I provided below. Rebasing the branch mentioned in that comment and testing that UI test, it seems that we actually end up only observing that `str: !Sized` during monomorphization, whereupon we ICE. Even if we were to fix that ICE, ideally we'd be raising an error that a fn pointer is being used badly during _typecheck_ instead of monomorphization, hence adapting the original approach in #83915.
I am happy to close this if people would prefer we rebase the original PR and land that -- I am partly opening to be annoying and get people thinking about this unsoundness again ❤️😸
cc: `@estebank` and `@nikomatsakis`
r? types
Here's a link to the thread: https://rust-lang.zulipchat.com/#narrow/stream/144729-t-types/topic/PR.20.2383915/near/235421351 for more context.
It's now much more like the `-Zhir-stats` output.
- Each line is preceded with `meta-stats`, which makes the provenance
clearer and allows filtering of the output.
- Sections are now sorted in reverse order of size.
- Column headings avoid the need to repeat the word "bytes" on every line.
- Long numbers now have `_` separators for easier reading.
- Consistent use of '-' within section labels, rather than a mix of '-',
'_', and ' '.
The code itself is shorter and easier to read thanks to:
- the `stat` macro, which encapsulates each section's encoding, avoids
some boilerplate, and removes the need for some low-value comments;
- the `stats` vector, which replaces dozens of local variables.
Optimize `array::IntoIter`
`.into_iter()` on arrays was slower than it needed to be (especially compared to slice iterator) since it uses `Range<usize>`, which needs to handle degenerate ranges like `10..4`.
This PR adds an internal `IndexRange` type that's like `Range<usize>` but with a safety invariant that means it doesn't need to worry about those cases -- it only handles `start <= end` -- and thus can give LLVM more information to optimize better.
I added one simple demonstration of the improvement as a codegen test.
(`vec::IntoIter` uses pointers instead of indexes, so doesn't have this problem, but that only works because its elements are boxed. `array::IntoIter` can't use pointers because that would keep it from being movable.)
This rule was added in 88fe6dfa31 to assist
in position the hide/show togges on methods. This is no longer needed,
because these toggles are no longer implemented as absolutely positioned
links nested inside headers.
This just prints a message but continues on if a fallback is missing,
which can happen when we're building a partial set of builders and
producing a dev-static build from it (e.g., when no Apple builder runs
at all).
Probably the more extensive fix is to allow the build-manifest invoker
to specify the expected set of targets & hosts, but that's a far more
extensive change. The main risk from this is that we accidentally start
falling back to linux docs across all platforms without noticing. I'm
not sure that we can do much about that though at this time.
std: use `sync::RwLock` for internal statics
Since `sync::RwLock` is now `const`-constructible, it can be used for internal statics, removing the need for `sys_common::StaticRwLock`. This adds some extra allocations on platforms which need to box their locks (currently SGX and some UNIX), but these will become unnecessary with the lock improvements tracked in #93740.
This patch updates sanitizier support definitions for Android inside the
compiler. It also adjusts the logic to make sure no pre-built sanitizer
runtime libraries are emitted as these are instead provided dynamically
on Android targets.
Make the `normalize-overflow` rustdoc test actually do something
Since https://github.com/rust-lang/rust/pull/88679, rustdoc doesn't load crates eagerly. Add an explicit `extern crate` item to make sure the crate is loaded and the bug reproduces.
You can verify this fix by adding `// compile-flags: -Znormalize-docs` and running the test to make sure it gives an error.
Improve error for when query is unsupported by crate
This is an improvement to the error message mentioned on #101666. It seems like a good idea to also add [this link to the rustc-dev-guide](https://rustc-dev-guide.rust-lang.org/query.html), if explaining the query system in detail is a concern here, but I'm unsure if there is any restrictions on adding links to error messages.
State up-front and center what shape the returned extension will have, without
making the user read through the description and examples.
Rationale: Various frameworks and libraries for different platforms have their
different conventions as to whether an "extension" is ".ext" or just "ext" and
anyone that's had to deal with this ambiguity in the past is always double- or
triple-checking to make sure the function call returns an extension that matches
the expected semantics. Offer the answer to this important question right off
the bat instead of making them dig to find it.
remove Windows TERM env var hack and -Zmiri-env-exclude
The hack should not be needed any more since https://github.com/rust-lang/rust/pull/100206. And that also mostly removes the need for `-Zmiri-env-exclude` -- if needed, users can still achieve the same by running `(unset VAR; cargo miri test)`.
I am keeping `-Zmiri-env-forward` since it is still useful, e.g. to have RUST_BACKTRACE=full set in an otherwise deterministic execution.
`@rust-lang/miri` any objections to removing `-Zmiri-env-exclude`?
avoid thread-local var indirection for non-halting diagnostics
This hack used to be necessary because Stacked Borrows did not have access to enough parts of the machine. But that got fixed a while ago, so now we can just emit diagnostics directly, which is a lot more reliable.
Needs https://github.com/rust-lang/rust/pull/101985
Fixes https://github.com/rust-lang/miri/issues/2538
