Disambiguate between SourceFiles from different crates even if they have the same path
This PR fixes an ICE that can occur when the compiler encounters a source file that is part of both the local crate and an upstream crate:
1. While importing source files from an upstream crate the compiler creates a `SourceFile` entry for `foo.rs` in the `SourceMap`. Since this is an imported source file its `src` field is `None`.
2. At a later point the parser encounters `foo.rs` again. It tells the `SourceMap` to load the file but because we already have an entry for `foo.rs` the `SourceMap` will return the existing version with `src == None`.
3. The parser proceeds under the assumption that `src.is_some()` and panics when actually trying to use the file's contents.
This PR fixes the issue by adding the source file's associated `CrateNum` to the `SourceMap`'s interning key. As a consequence the two instances of the file will each have a separate entry in the `SourceMap`. They just happen to share the same file path. This approach seemed less problematic to me than trying to mutate the `SourceFile` after it had already been created.
Another, more involved, approach might be to merge the `src` and the `external_src` field.
Fixes#85955
Fix `unused_unsafe` around `await`
Enables `unused_unsafe` lint for `unsafe { future.await }`.
The existing test for this is `unsafe { println!() }`, so I assume that `println!` used to contain compiler-generated unsafe but this is no longer true, and so the existing test is broken. I replaced the test with `unsafe { ...await }`. I believe `await` is currently the only instance of compiler-generated unsafe.
Reverts some parts of #85421, but the issue predates that PR.
make UB during CTFE a hard error
This is a next step for https://github.com/rust-lang/rust/issues/71800. `const_err` has been a future-incompatibility lint for 4 months now since https://github.com/rust-lang/rust/pull/80394 (and err-by-default for many years before that), so I think we could try making it a proper hard error at least in some situations.
I didn't yet adjust the tests, since I first want to gauge the fall-out via crater.
Cc `@rust-lang/wg-const-eval`
Remove some last remants of {push,pop}_unsafe!
These macros have already been removed, but there was still some code handling these macros. That code is now removed.
Use better error message for hard errors in CTFE
I noticed this while working on #86255: currently the same message is used for hard errors and soft errors in CTFE. This changes the error messages to make hard errors use a message that indicates the reality of the situation correctly, since usage of the constant is never allowed when there was a hard error evaluating it. This doesn't affect the behaviour of these error messages, only the content.
This changes the error logic to check if the error should be hard or soft where it is generated, instead of where it is emitted, to allow this distinction in error messages.
Box `thir::ExprKind::Adt` for performance
`Adt` is the biggest variant in the enum and probably isn't used very often compared to the other expr kinds, so boxing it should be beneficial for performance. We need a perf test to be sure.
Refactor vtable codegen
This refactor the codegen of vtables of miri interpreter, llvm, cranelift codegen backends.
This is preparation for the implementation of trait upcasting feature. cc #65991
Note that aside from code reorganization, there's an internal behavior change here that now InstanceDef::Virtual's index now include the three metadata slots, and now the first method is with index 3.
cc `@RalfJung` `@bjorn3`
Fix ICEs on invalid vtable size/alignment const UB errors
The invalid vtable size/alignment errors from `InterpCx::read_size_and_align_from_vtable` were "freeform const UB errors", causing ICEs when reaching validation. This PR turns them into const UB hard errors to catch them during validation and avoid that.
Fixes#86193
r? `@RalfJung`
(It seemed cleaner to have 2 variants but they can be merged into one variant with a message payload if you prefer that ?)
Hash DefId in rustc_span.
This is mostly just moving code around. Changes are simplifications of unneeded callbacks from rustc_span to rustc_middle.
r? `@petrochenkov`
Make `relate_type_and_mut` public
#85343 improved diagnostics around `Relate` impls but made `relate_type_and_mut` private, which was accessible as `relate` previously. This makes it public so that we can use it on rust-semverver.
r? ```@Aaron1011```
Fix some diagnostic issues with const_generics_defaults feature gate
This PR makes a few changes:
- print out const param defaults in "lifetime ordering" errors rather than discarding them
- update `is_simple_text` to account for const params when checking if a type has no generics, this was causing a note to be failed to add to an error message
- fixes some diagnostic wording that incorrectly said there was ordering restrictions between type/const params despite the `const_generics_defaults` feature gate is active
