Fix promotion in a `const` when projections are present
Resolves#65727.
This marks the entire local as "needs promotion" when only a projection of that local appears in a promotable context. This should only affect promotion in a `const` or `static`, not in a `fn` or `const fn`, which is handled in `promote_consts.rs`.
r? @eddyb
The old const-checker conservatively reset qualifs when
`IsNotPromotable` was in the return place. Unfortunately, named
variables have `IsNotPromotable`, so this could cause promotion to fail.
This should work now.
The former was cleared from `qualifs_in_return_place`, and the latter
was never checked. `QUALIF_ERROR_BIT` no longer corresponds to a real
`Qualif`, however.
We no longer compare the results of
`promote_consts::validate_candidates` with
`checker.promotion_candidates`, and `promote_consts` becomes the
canonical source for determining promotability.
As we might want to add `IntoIterator` impls for arrays in the future,
and since that introduces a breaking change, this lint warns and
suggests using `iter()` instead (which is shorter and more explicit).
`AttrKind` is a new type with two variants, `Normal` and `DocComment`. It's a
big performance win (over 10% in some cases) because `DocComment` lets doc
comments (which are common) be represented very cheaply.
`Attribute` gets some new helper methods to ease the transition:
- `has_name()`: check if the attribute name matches a single `Symbol`; for
`DocComment` variants it succeeds if the symbol is `sym::doc`.
- `is_doc_comment()`: check if it has a `DocComment` kind.
- `{get,unwrap}_normal_item()`: extract the item from a `Normal` variant;
panic otherwise.
Fixes#60935.
Use ident.span instead of def_span in dead-code pass
Hello! First time contributor! :)
This should fix#58729.
According to @estebank in the duplicate #63064, def_span scans forward on the line until it finds a {,
and if it can't find one, falls back to the span for the whole item. This
was apparently written before the identifier span was explicitly tracked on
each node.
This means that if an unused function signature spans multiple lines, the
entire function (potentially hundreds of lines) gets flagged as dead code.
This could, for example, cause IDEs to add error squiggly's to the whole
function.
By using the span from the ident instead, we narrow the scope of this in
most cases. In a wider sense, it's probably safe to use ident.span
instead of def_span in most locations throughout the whole code base,
but since this is my first contribution, I kept it small.
Some interesting points that came up while I was working on this:
- I reorganized the tests a bit to bring some of the dead code ones all
into the same location
- A few tests were for things unrelated to dead code (like the
path-lookahead for parens), so I added #![allow(dead_code)] and
cleaned up the stderr file to reduce noise in the future
- The same fix doesn't apply to const and static declarations. I tried
adding these cases to the match expression, but that created a much
wider change to tests and error messages, so I left it off until I
could get some code review to validate the approach.
Rollup of 9 pull requests
Successful merges:
- #65776 (Rename `LocalInternedString` and more)
- #65973 (caller_location: point to macro invocation sites, like file!/line!, and use in core::panic!.)
- #66015 (librustc_lexer: Refactor the module)
- #66062 (Configure LLVM module PIC level)
- #66086 (bump smallvec to 1.0)
- #66092 (Use KERN_ARND syscall for random numbers on NetBSD, same as FreeBSD.)
- #66103 (Add target thumbv7neon-unknown-linux-musleabihf)
- #66133 (Update the bundled `wasi-libc` repository)
- #66139 (use American spelling for `pluralize!`)
Failed merges:
r? @ghost
Update the bundled `wasi-libc` repository
This updates the libc that the `wasm32-wasi` target links against to the
latest revision, mostly just bringing in minor bug fixes and minor wasm
size improvements.
Add target thumbv7neon-unknown-linux-musleabihf
This is a copy of thumbv7neon-unknown-linux-gnueabihf with musl changes
merged from armv7-unknown-linux-musleabihf. This appears to have been
missed when adding the other ARMv7-A thumb targets.
Use KERN_ARND syscall for random numbers on NetBSD, same as FreeBSD.
This system call is present on all supported NetBSD versions and provides an endless stream of non-blocking random data from the kernel's ChaCha20-based CSPRNG. It doesn't require a file like `/dev/urandom` to be opened.
The system call is documented here (under kern.arandom):
https://netbsd.gw.com/cgi-bin/man-cgi?sysctl+7+NetBSD-7.0
And defined here:
https://nxr.netbsd.org/xref/src/sys/sys/sysctl.h#273
The semantics are the same as FreeBSD so reading 256 bytes per call is fine.
Similar change for getrandom crate: rust-random/getrandom#115
