Split coroutine desugaring kind from source
What a coroutine is desugared from (gen/async gen/async) should be separate from where it comes (fn/block/closure).
There are only three. It's simpler to make the type
`DiagnosticBuilder<'_, ()>` from the start, no matter the level, than to
change the guarantee later.
Lots of vectors of messages called `message` or `msg`. This commit
pluralizes them.
Note that `emit_message_default` and `emit_messages_default` both
already existed, and both process a vector, so I renamed the former
`emit_messages_default_inner` because it's called by the latter.
rustc_codegen_ssa: Don't drop `IncorrectCguReuseType` , make `rustc_expected_cgu_reuse` attr work
In [100753], `IncorrectCguReuseType` accidentally stopped being emitted by removing `diag.span_err(...)`. Begin emitting it again rather than just blindly dropping it, and adjust tests accordingly.
We assume that there are no bugs and that the currently actual CGU reuse is correct. If there are bugs, they will be discovered and fixed eventually, and the tests will then be updated.
[100753]: 706452eba7 (diff-048389738ddcbe0f9765291a29db1fed9a5f03693d4781cfb5aaa97ffb3c7f84)Closes#118972
And make all hand-written `IntoDiagnostic` impls generic, by using
`DiagnosticBuilder::new(dcx, level, ...)` instead of e.g.
`dcx.struct_err(...)`.
This means the `create_*` functions are the source of the error level.
This change will let us remove `struct_diagnostic`.
Note: `#[rustc_lint_diagnostics]` is added to `DiagnosticBuilder::new`,
it's necessary to pass diagnostics tests now that it's used in
`into_diagnostic` functions.
[AIX] Fix XCOFF metadata
#118344 accidentally changed the way to get metadata from XCOFF file and broken our internal CI.
This PR reverts part of #118344 .
Add all known `target_feature` configs to check-cfg
This PR adds all the known `target_feature` from ~~`rustc_codegen_ssa`~~ `rustc_target` to the well known list of check-cfg.
It does so by moving the list from `rustc_codegen_ssa` to `rustc_target` ~~`rustc_session` (I not sure about this, but some of the moved function take a `Session`)~~, then using it the `fill_well_known` function.
This already proved to be useful since portable-simd had a bad cfg.
cc `@nnethercote` (since we discussed it in https://github.com/rust-lang/rust/pull/118494)
Currently, `emit_diagnostic` takes `&mut self`.
This commit changes it so `emit_diagnostic` takes `self` and the new
`emit_diagnostic_without_consuming` function takes `&mut self`.
I find the distinction useful. The former case is much more common, and
avoids a bunch of `mut` and `&mut` occurrences. We can also restrict the
latter with `pub(crate)` which is nice.
rustc_codegen_ssa: Remove trailing spaces in Display impl for CguReuse
Otherwise errors will look like this:
error: CGU-reuse for `cgu_invalidated_via_import-bar` is `PreLto ` but should be `PostLto `
### Background
I noticed that error messages looked wonky while investigating if
529047cfc3/compiler/rustc_codegen_ssa/src/assert_module_sources.rs (L281-L287)
should not be wrapped by `sess.emit_err(...)`. Right now it looks like the error is accidentally ignored. It looks like 706452eba7 might have accidentally started ignoring it (by removing the `diag.span_err()` call). I am still investigating, but regardless of the outcome we should fix the trailing whitespace.
codegen: panic when trying to compute size/align of extern type
The alignment is also computed when accessing a field of extern type at non-zero offset, so we also panic in that case.
Previously `size_of_val` worked because the code path there assumed that "thin pointer" means "sized". But that's not true any more with extern types. The returned size and align are just blatantly wrong, so it seems better to panic than returning wrong results. We use a non-unwinding panic since code probably does not expect size_of_val to panic.
Use a u64 for the rmeta root position
Waffle noticed this in https://github.com/rust-lang/rust/pull/117301#discussion_r1405410174
We've upgraded the other file offsets to u64, and this one only costs 4 bytes per file. Also the way the truncation was being done before was extremely easy to miss, I sure missed it! It's not clear to me if not having this change effectively made the other upgrades from u32 to u64 ineffective, but we can have it now.
r? `@WaffleLapkin`
detects redundant imports that can be eliminated.
for #117772 :
In order to facilitate review and modification, split the checking code and
removing redundant imports code into two PR.
update target feature following LLVM API change
LLVM commit e817966718 renamed* the `unaligned-scalar-mem` target feature to `fast-unaligned-access`.
(*) technically the commit folded two previous features into one, but there are no references to the other one in rust.
Add emulated TLS support
This is a reopen of https://github.com/rust-lang/rust/pull/96317 . many android devices still only use 128 pthread keys, so using emutls can be helpful.
Currently LLVM uses emutls by default for some targets (such as android, openbsd), but rust does not use it, because `has_thread_local` is false.
This commit has some changes to allow users to enable emutls:
1. add `-Zhas-thread-local` flag to specify that std uses `#[thread_local]` instead of pthread key.
2. when using emutls, decorate symbol names to find thread local symbol correctly.
3. change `-Zforce-emulated-tls` to `-Ztls-model=emulated` to explicitly specify whether to generate emutls.
r? `@Amanieu`
Avoid adding builtin functions to `symbols.o`
We found performance regressions in #113923. The problem seems to be that `--gc-sections` does not remove these symbols. I tested that lld removes these symbols, but ld and gold do not.
I found that `used` adds symbols to `symbols.o` at 3e202ead60/compiler/rustc_codegen_ssa/src/back/linker.rs (L1786-L1791).
The PR removes builtin functions.
Note that under LTO, ld still preserves these symbols. (lld will still remove them.)
The first commit also fixes#118559. But I think the second commit also makes sense.
compile-time evaluation: detect writes through immutable pointers
This has two motivations:
- it unblocks https://github.com/rust-lang/rust/pull/116745 (and therefore takes a big step towards `const_mut_refs` stabilization), because we can now detect if the memory that we find in `const` can be interned as "immutable"
- it would detect the UB that was uncovered in https://github.com/rust-lang/rust/pull/117905, which was caused by accidental stabilization of `copy` functions in `const` that can only be called with UB
When UB is detected, we emit a future-compat warn-by-default lint. This is not a breaking change, so completely in line with [the const-UB RFC](https://rust-lang.github.io/rfcs/3016-const-ub.html), meaning we don't need t-lang FCP here. I made the lint immediately show up for dependencies since it is nearly impossible to even trigger this lint without `const_mut_refs` -- the accidentally stabilized `copy` functions are the only way this can happen, so the crates that popped up in #117905 are the only causes of such UB (in the code that crater covers), and the three cases of UB that we know about have all been fixed in their respective crates already.
The way this is implemented is by making use of the fact that our interpreter is already generic over the notion of provenance. For CTFE we now use the new `CtfeProvenance` type which is conceptually an `AllocId` plus a boolean `immutable` flag (but packed for a more efficient representation). This means we can mark a pointer as immutable when it is created as a shared reference. The flag will be propagated to all pointers derived from this one. We can then check the immutable flag on each write to reject writes through immutable pointers.
I just hope perf works out.
Currently LLVM uses emutls by default
for some targets (such as android, openbsd),
but rust does not use it, because `has_thread_local` is false.
This commit has some changes to allow users to enable emutls:
1. add `-Zhas-thread-local` flag to specify
that std uses `#[thread_local]` instead of pthread key.
2. when using emutls, decorate symbol names
to find thread local symbol correctly.
3. change `-Zforce-emulated-tls` to `-Ztls-model=emulated`
to explicitly specify whether to generate emutls.
rustc: Harmonize `DefKind` and `DefPathData`
Follow up to https://github.com/rust-lang/rust/pull/118188.
`DefPathData::(ClosureExpr,ImplTrait)` are renamed to match `DefKind::(Closure,OpaqueTy)`.
`DefPathData::ImplTraitAssocTy` is replaced with `DefPathData::TypeNS(kw::Empty)` because both correspond to `DefKind::AssocTy`.
It's possible that introducing `(DefKind,DefPathData)::AssocOpaqueTy` instead could be a better solution, but that would be a much more invasive change.
Const generic parameters introduced for effects are moved from `DefPathData::TypeNS` to `DefPathData::ValueNS`, because constants are values.
`DefPathData` is no longer passed to `create_def` functions to avoid redundancy.
more targeted errors when extern types end up in places they should not
Cc https://github.com/rust-lang/rust/issues/115709 -- this does not fix that bug but it makes the panics less obscure and makes it more clear that this is a deeper issue than just a little codegen oversight. (In https://github.com/rust-lang/rust/pull/116115 we decided we'd stick to causing ICEs here for now, rather than nicer errors. We can't currently show any errors pre-mono and probably we don't want post-mono checks when this gets stabilized anyway.)