Support #[global_allocator] without the allocator shim
This makes it possible to use liballoc/libstd in combination with `--emit obj` if you use `#[global_allocator]`. This is what rust-for-linux uses right now and systemd may use in the future. Currently they have to depend on the exact implementation of the allocator shim to create one themself as `--emit obj` doesn't create an allocator shim.
Note that currently the allocator shim also defines the oom error handler, which is normally required too. Once `#![feature(default_alloc_error_handler)]` becomes the only option, this can be avoided. In addition when using only fallible allocator methods and either `--cfg no_global_oom_handling` for liballoc (like rust-for-linux) or `--gc-sections` no references to the oom error handler will exist.
To avoid this feature being insta-stable, you will have to define `__rust_no_alloc_shim_is_unstable` to avoid linker errors.
(Labeling this with both T-compiler and T-lang as it originally involved both an implementation detail and had an insta-stable user facing change. As noted above, the `__rust_no_alloc_shim_is_unstable` symbol requirement should prevent unintended dependence on this unstable feature.)
Rather than returning an array of features from to_llvm_features, return a structure that contains
the dependencies. This also contains metadata on how the features depend on each other to allow for
the correct enabling and disabling.
Some features that are tied together only make sense to be folded
together when enabling the feature. For example on AArch64 sve and
neon are tied together, however it doesn't make sense to disable neon
when disabling sve.
In #91608 the fp-armv8 feature was removed as it's tied to the neon
feature. However disabling neon didn't actually disable the use of
floating point registers and instructions, for this `-fp-armv8` is
required.
Fix dependency tracking for debugger visualizers
This PR fixes dependency tracking for debugger visualizer files by changing the `debugger_visualizers` query to an `eval_always` query that scans the AST while it is still available. This way the set of visualizer files is already available when dep-info is emitted. Since the query is turned into an `eval_always` query, dependency tracking will now reliably detect changes to the visualizer script files themselves.
TODO:
- [x] perf.rlo
- [x] Needs a bit more documentation in some places
- [x] Needs regression test for the incr. comp. case
Fixes https://github.com/rust-lang/rust/issues/111226
Fixes https://github.com/rust-lang/rust/issues/111227
Fixes https://github.com/rust-lang/rust/issues/111295
r? `@wesleywiser`
cc `@gibbyfree`
Only depend on CFG_VERSION in rustc_interface
This avoids having to rebuild the whole compiler on each commit when `omit-git-hash = false`.
cc https://github.com/rust-lang/rust/issues/76720 - this won't fix it, and I'm not suggesting we turn this on by default, but it will make it less painful for people who do have `omit-git-hash` on as a workaround.
Remove the ThinLTO CU hack
This reverts #46722, commit e0ab5d5feb4eb2d8af11b8dd9446c2b45fada8af.
Since #111167, commit 10b69dde3fd15334ea2382d2dc9e9a261de1afaf, we are
generating DWARF subprograms in a way that is meant to be more compatible
with LLVM's expectations, so hopefully we don't need this workaround
rewriting CUs anymore.
Remove misleading target feature aliases
Fixes#100752. This is a follow up to #103750. These aliases could not be completely removed until rust-lang/stdarch#1355 landed.
cc `@Amanieu`
CFI: Fix SIGILL reached via trait objects
Fix#106547 by transforming the concrete self into a reference to a trait object before emitting type metadata identifiers for trait methods.
You will need to add the following as replacement for the old __rust_*
definitions when not using the alloc shim.
#[no_mangle]
static __rust_no_alloc_shim_is_unstable: u8 = 0;
This makes it possible to use liballoc/libstd in combination with
`--emit obj` if you use `#[global_allocator]`. Making it work for the
default libstd allocator would require weak functions, which are not
well supported on all systems.
This reverts #46722, commit e0ab5d5feb4eb2d8af11b8dd9446c2b45fada8af.
Since #111167, commit 10b69dde3fd15334ea2382d2dc9e9a261de1afaf, we are
generating DWARF subprograms in a way that is meant to be more compatible
with LLVM's expectations, so hopefully we don't need this workaround
rewriting CUs anymore.
Mark s390x condition code register as clobbered in inline assembly
Various s390x instructions (arithmetic operations, logical operations, comparisons, etc. see also "Condition Codes" section in [z/Architecture Reference Summary](https://www.ibm.com/support/pages/zarchitecture-reference-summary)) modify condition code register `cc`, but AFAIK there is currently no way to mark it as clobbered in `asm!`.
`cc` register definition in LLVM:
https://github.com/llvm/llvm-project/blob/main/llvm/lib/Target/SystemZ/SystemZRegisterInfo.td#L320
This PR also updates asm_experimental_arch docs in the unstable-book to mention s390x registers.
cc `@uweigand`
r? `@Amanieu`
Output LLVM optimization remark kind in `-Cremark` output
Since https://github.com/rust-lang/rust/pull/90833, the optimization remark kind has not been printed. Therefore it wasn't possible to easily determine from the log (in a programmatic way) which remark kind was produced. I think that the most interesting remarks are the missed ones, which can lead users to some code optimization.
Maybe we could also change the format closer to the "old" one:
```
note: optimization remark for tailcallelim at /checkout/src/libcore/num/mod.rs:1:0: marked this call a tail call candidate
```
I wanted to programatically parse the remarks so that they could work e.g. with https://github.com/OfekShilon/optview2. However, now that I think about it, probably the proper solution is to tell rustc to output them to YAML and then use the YAML as input for the opt remark visualization tools. The flag for enabling this does not seem to work though (https://github.com/rust-lang/rust/issues/96705#issuecomment-1117632322).
Still I think that it's good to output the remark kind anyway, it's an important piece of information.
r? ```@tmiasko```
debuginfo: split method declaration and definition
When we're adding a method to a type DIE, we only want a DW_AT_declaration
there, because LLVM LTO can't unify type definitions when a child DIE is a
full subprogram definition. Now the subprogram definition gets added at the
CU level with a specification link back to the abstract declaration.
Both GCC and Clang write debuginfo this way for C++ class methods.
Fixes#109730.
Fixes#109934.
Stabilize raw-dylib, link_ordinal, import_name_type and -Cdlltool
This stabilizes the `raw-dylib` feature (#58713) for all architectures (i.e., `x86` as it is already stable for all other architectures).
Changes:
* Permit the use of the `raw-dylib` link kind for x86, the `link_ordinal` attribute and the `import_name_type` key for the `link` attribute.
* Mark the `raw_dylib` feature as stable.
* Stabilized the `-Zdlltool` argument as `-Cdlltool`.
* Note the path to `dlltool` if invoking it failed (we don't need to do this if `dlltool` returns an error since it prints its path in the error message).
* Adds tests for `-Cdlltool`.
* Adds tests for being unable to find the dlltool executable, and dlltool failing.
* Fixes a bug where we were checking the exit code of dlltool to see if it failed, but dlltool always returns 0 (indicating success), so instead we need to check if anything was written to `stderr`.
NOTE: As previously noted (https://github.com/rust-lang/rust/pull/104218#issuecomment-1315895618) using dlltool within rustc is temporary, but this is not the first time that Rust has added a temporary tool use and argument: https://github.com/rust-lang/rust/pull/104218#issuecomment-1318720482
Big thanks to ``````@tbu-`````` for the first version of this PR (#104218)
Add cross-language LLVM CFI support to the Rust compiler
This PR adds cross-language LLVM Control Flow Integrity (CFI) support to the Rust compiler by adding the `-Zsanitizer-cfi-normalize-integers` option to be used with Clang `-fsanitize-cfi-icall-normalize-integers` for normalizing integer types (see https://reviews.llvm.org/D139395).
It provides forward-edge control flow protection for C or C++ and Rust -compiled code "mixed binaries" (i.e., for when C or C++ and Rust -compiled code share the same virtual address space). For more information about LLVM CFI and cross-language LLVM CFI support for the Rust compiler, see design document in the tracking issue #89653.
Cross-language LLVM CFI can be enabled with -Zsanitizer=cfi and -Zsanitizer-cfi-normalize-integers, and requires proper (i.e., non-rustc) LTO (i.e., -Clinker-plugin-lto).
Thank you again, ``@bjorn3,`` ``@nikic,`` ``@samitolvanen,`` and the Rust community for all the help!
When we're adding a method to a type DIE, we only want a DW_AT_declaration
there, because LLVM LTO can't unify type definitions when a child DIE is a
full subprogram definition. Now the subprogram definition gets added at the
CU level with a specification link back to the abstract declaration.
This commit adds cross-language LLVM Control Flow Integrity (CFI)
support to the Rust compiler by adding the
`-Zsanitizer-cfi-normalize-integers` option to be used with Clang
`-fsanitize-cfi-icall-normalize-integers` for normalizing integer types
(see https://reviews.llvm.org/D139395).
It provides forward-edge control flow protection for C or C++ and Rust
-compiled code "mixed binaries" (i.e., for when C or C++ and Rust
-compiled code share the same virtual address space). For more
information about LLVM CFI and cross-language LLVM CFI support for the
Rust compiler, see design document in the tracking issue #89653.
Cross-language LLVM CFI can be enabled with -Zsanitizer=cfi and
-Zsanitizer-cfi-normalize-integers, and requires proper (i.e.,
non-rustc) LTO (i.e., -Clinker-plugin-lto).
Report allocation errors as panics
OOM is now reported as a panic but with a custom payload type (`AllocErrorPanicPayload`) which holds the layout that was passed to `handle_alloc_error`.
This should be review one commit at a time:
- The first commit adds `AllocErrorPanicPayload` and changes allocation errors to always be reported as panics.
- The second commit removes `#[alloc_error_handler]` and the `alloc_error_hook` API.
ACP: https://github.com/rust-lang/libs-team/issues/192Closes#51540Closes#51245
