Rust recently introduced a new `unused_imports` warning
in `no_fp_fmt_parse` builds, which was fixed in
https://github.com/rust-lang/rust/pull/105434.
To avoid accumulating more over time, let's keep the builds
warning-free. This ensures projects compiling `core` with
this custom config do not see the warnings in the future
and that they can keep enabling `-Dwarnings`.
Similarly, https://github.com/rust-lang/rust/pull/98652 did it
for `alloc`'s `no_global_oom_handling`.
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
When running tests inside the Android emulator, bootstrap doesn't set
the TEST_DEVICE_ADDR environment variable, as the default address
(127.0.0.1:12345) is used.
Instead, REMOTE_TEST_CLIENT is set all the times when remote testing is
needed, and in no other cases. To ensure Android tests are executed in
the emulator, change the check.
llvm: dwo only emitted when object code emitted
Fixes#103932.
`CompiledModule` should not think a DWARF object was emitted when a bitcode-only compilation has happened, this can confuse archive file creation (which expects to create an archive containing non-existent dwo files).
r? ``````@michaelwoerister``````
`CompiledModule` should not think a DWARF object was emitted when a
bitcode-only compilation has happened, this can confuse archive file
creation (which expects to create an archive containing non-existent dwo
files).
Signed-off-by: David Wood <david.wood@huawei.com>
libtest: run all tests in their own thread, if supported by the host
This reverts the threading changes of https://github.com/rust-lang/rust/pull/56243, which made it so that with `-j1`, the test harness does not spawn any threads. Those changes were done to enable Miri to run the test harness, but Miri supports threads nowadays, so this is no longer needed. Using a thread for each test is useful because the thread's name can be set to the test's name which makes panic messages consistent between `-j1` and `-j2` runs and also a bit more readable.
I did not revert the HashMap changes of https://github.com/rust-lang/rust/pull/56243; using a deterministic map seems fine for the test harness and the more deterministic testing is the better.
Fixes https://github.com/rust-lang/rust/issues/59122
Fixes https://github.com/rust-lang/rust/issues/70492
The new implementation doesn't use weak lang items and instead changes
`#[alloc_error_handler]` to an attribute macro just like
`#[global_allocator]`.
The attribute will generate the `__rg_oom` function which is called by
the compiler-generated `__rust_alloc_error_handler`. If no `__rg_oom`
function is defined in any crate then the compiler shim will call
`__rdl_oom` in the alloc crate which will simply panic.
This also fixes link errors with `-C link-dead-code` with
`default_alloc_error_handler`: `__rg_oom` was previously defined in the
alloc crate and would attempt to reference the `oom` lang item, even if
it didn't exist. This worked as long as `__rg_oom` was excluded from
linking since it was not called.
This is a prerequisite for the stabilization of
`default_alloc_error_handler` (#102318).
Rename some `OwnerId` fields.
`@spastorino` noticed some silly expressions like `item_id.def_id.def_id`.
This commit renames several `def_id: OwnerId` fields as `owner_id`, so those expressions become `item_id.owner_id.def_id`.
`item_id.owner_id.local_def_id` would be even clearer, but the use of `def_id` for values of type `LocalDefId` is *very* widespread, so I left that alone.
r? `@compiler-errors`
spastorino noticed some silly expressions like `item_id.def_id.def_id`.
This commit renames several `def_id: OwnerId` fields as `owner_id`, so
those expressions become `item_id.owner_id.def_id`.
`item_id.owner_id.local_def_id` would be even clearer, but the use of
`def_id` for values of type `LocalDefId` is *very* widespread, so I left
that alone.
This PR will fix some typos detected by [typos].
I only picked the ones I was sure were spelling errors to fix, mostly in
the comments.
[typos]: https://github.com/crate-ci/typos
Move EH personality functions to std
These were previously in the panic_unwind crate with dummy stubs in the
panic_abort crate. However it turns out that this is insufficient: we
still need a proper personality function even with -C panic=abort to
handle the following cases:
1) `extern "C-unwind"` still needs to catch foreign exceptions with -C
panic=abort to turn them into aborts. This requires landing pads and a
personality function.
2) ARM EHABI uses the personality function when creating backtraces.
The dummy personality function in panic_abort was causing backtrace
generation to get stuck in a loop since the personality function is
responsible for advancing the unwind state to the next frame.
Fixes#41004
session: stabilize split debuginfo on linux
Stabilize the `-Csplit-debuginfo` flag...
- ...on Linux for all values of the flag. Split DWARF has been implemented for a few months, hasn't had any bug reports and has had some promising benchmarking for incremental debug build performance.
- ..on other platforms for the default value. It doesn't make any sense that `-Csplit-debuginfo=packed` is unstable on Windows MSVC when that's the default behaviour, but keep the other values unstable.
In Rust for Linux we are using these to make `alloc` a bit
more modular.
A `run-make-fulldeps` test is added for each of them, so that
enabling each of them independently is kept in a compilable state.
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Stabilize the `-Csplit-debuginfo` flag...
- ...on Linux for all values of the flag. Split DWARF has been
implemented for a few months, hasn't had any bug reports and has had
some promising benchmarking for incremental debug build performance.
- ..on other platforms for the default value. It doesn't make any sense
that `-Csplit-debuginfo=packed` is unstable on Windows MSVC when
that's the default behaviour, but keep the other values unstable.
Signed-off-by: David Wood <david.wood@huawei.com>
Stabilize backtrace
This PR stabilizes the std::backtrace module. As of #99431, the std::Error::backtrace item has been removed, and so the rest of the backtrace feature is set to be stabilized.
Previous discussion can be found in #72981, #3156.
Stabilized API summary:
```rust
pub mod std {
pub mod backtrace {
pub struct Backtrace { }
pub enum BacktraceStatus {
Unsupported,
Disabled,
Captured,
}
impl fmt::Debug for Backtrace {}
impl Backtrace {
pub fn capture() -> Backtrace;
pub fn force_capture() -> Backtrace;
pub const fn disabled() -> Backtrace;
pub fn status(&self) -> BacktraceStatus;
}
impl fmt::Display for Backtrace {}
}
}
```
`@yaahc`
Prior work, notably 6550021124 from #88316
has removed box syntax from most of the testsuite. However,
some tests were left out.
This commit removes box_syntax uses from more locations in src/test.
Some tests that are very box syntax specific are not being migrated.
Only __rustc_proc_macro_decls_*__ and rust_metadata_* need to be
exported for proc macros to work. All other symbols only increase binary
size and have the potential to conflict with symbols from the host
compiler.
Enable raw-dylib for bin crates
Fixes#93842
When `raw-dylib` is used in a `bin` crate, we need to collect all of the `raw-dylib` functions, generate the import library and add that to the linker command line.
I also changed the tests so that 1) the C++ dlls are created after the Rust dlls, thus there is no chance of accidentally using them in the Rust linking process and 2) disabled generating import libraries when building with MSVC.
Remove reachable coverage without counters to maintain invariant that
either there is no coverage at all or there is a live coverage counter
left that provides the function source hash.
The motivating example would be a following closure:
```rust
let f = |x: bool| {
debug_assert!(x);
};
```
Which, with span changes from #93967, with disabled debug assertions,
after the final CFG simplifications but before removal of dead blocks,
gives rise to MIR:
```rust
fn main::{closure#0}(_1: &[closure@a.rs:2:13: 2:22], _2: bool) -> () {
debug x => _2;
let mut _0: ();
bb0: {
Coverage::Expression(4294967295) = 1 - 2;
return;
}
...
}
```
Fix unreachable coverage generation for inlined functions
To generate a function coverage we need at least one coverage counter,
so a coverage from unreachable blocks is retained only when some live
counters remain.
The previous implementation incorrectly retained unreachable coverage,
because it didn't account for the fact that those live counters can
belong to another function due to inlining.
Fixes#98833.
Allow to disable thinLTO buffer to support lto-embed-bitcode lld feature
Hello
This change is to fix issue (https://github.com/rust-lang/rust/issues/84395) in which passing "-lto-embed-bitcode=optimized" to lld when linking rust code via linker-plugin-lto doesn't produce the expected result.
Instead of emitting a single unified module into a llvmbc section of the linked elf, it emits multiple submodules.
This is caused because rustc emits the BC modules after running llvm `createWriteThinLTOBitcodePass` pass.
Which in turn triggers a thinLTO linkage and causes the said issue.
This patch allows via compiler flag (-Cemit-thin-lto=<bool>) to select between running `createWriteThinLTOBitcodePass` and `createBitcodeWriterPass`.
Note this pattern of selecting between those 2 passes is common inside of LLVM code.
The default is to match the old behavior.
Only compile #[used] as llvm.compiler.used for ELF targets
This returns `#[used]` to how it worked prior to the LLVM 13 update. The intention is not that this is a stable promise.
I'll add tests later today. The tests will test things that we don't actually promise, though.
It's a deliberately small patch, mostly comments. And assuming it's reviewed and lands in time, IMO it should at least be considered for uplifting to beta (so that it can be in 1.59), as the change broke many crates in the ecosystem, even if they are relying on behavior that is not guaranteed.
# Background
LLVM has two ways of preventing removal of an unused variable: `llvm.compiler.used`, which must be present in object files, but allows the linker to remove the value, and `llvm.used` which is supposed to apply to the linker as well, if possible.
Prior to LLVM 13, `llvm.used` and `llvm.compiler.used` were the same on ELF targets, although they were different elsewhere. Prior to our update to LLVM 13, we compiled `#[used]` using `llvm.used` unconditionally, even though we only ever promised behavior like `llvm.compiler.used`.
In LLVM 13, ELF targets gained some support for preventing linker removal of `llvm.used` via the SHF_RETAIN section flag. This has some compatibility issues though: Concretely: some older versions `ld.gold` (specifically ones prior to v2.36, released in Jan 2021) had a bug where it would fail to place a `#[used] #[link_section = ".init_array"]` static in between `__init_array_start`/`__init_array_end`, leading to code that does this failing to run a static constructor. This is technically not a thing we guarantee will work, is a common use case, and is needed in `libstd` (for example, to get access to `std::env::args()` even if Rust does not control `main`, such as when in a `cdylib` crate).
As a result, when updating to LLVM 13, we unconditionally switched to using `llvm.compiler.used`, which mirror the guarantees we make for `#[used]` and doesn't require the latest ld.gold. Unfortunately, this happened to break quite a bit of things in the ecosystem, as non-ELF targets had come to rely on `#[used]` being slightly stronger. In particular, there are cases where it will even break static constructors on these targets[^initinit] (and in fact, breaks way more use cases, as Mach-O uses special sections as an interface to the OS/linker/loader in many places).
As a result, we only switch to `llvm.compiler.used` on ELF[^elfish] targets. The rationale here is:
1. It is (hopefully) identical to the semantics we used prior to the LLVM13 update as prior to that update we unconditionally used `llvm.used`, but on ELF `llvm.used` was the same as `llvm.compiler.used`.
2. It seems to be how Clang compiles this, and given that they have similar (but stronger) compatibility promises, that makes sense.
[^initinit]: For Mach-O targets: It is not always guaranteed that `__DATA,__mod_init_func` is a GC root if it does not have the `S_MOD_INIT_FUNC_POINTERS` flag which we cannot add. In most cases, when ld64 transformed this section into `__DATA_CONST,__mod_init_func` it gets applied, but it's not clear that that is intentional (let alone guaranteed), and the logic is complex enough that it probably happens sometimes, and people in the wild report it occurring.
[^elfish]: Actually, there's not a great way to tell if it's ELF, so I've approximated it.
This is pretty ad-hoc and hacky! We probably should have a firmer set of guarantees here, but this change should relax the pressure on coming up with that considerably, returning it to previous levels.
---
Unsure who should review so leaving it open, but for sure CC `@nikic`
Stop keeping metadata in memory before writing it to disk
Fixes#96358
I created this PR according with the instruction given in the issue except for the following points:
- While the issue says "Write metadata into the temporary file in `encode_and_write_metadata` even if `!need_metadata_file`", I could not do that. That is because though I tried to do that and run `x.py test`, I got a lot of test failures as follows.
<details>
<summary>List of failed tests</summary>
<pre>
<code>
failures:
[ui] src/test/ui/json-multiple.rs
[ui] src/test/ui/json-options.rs
[ui] src/test/ui/rmeta/rmeta-rpass.rs
[ui] src/test/ui/save-analysis/emit-notifications.rs
[ui] src/test/ui/svh/changing-crates.rs
[ui] src/test/ui/svh/svh-change-lit.rs
[ui] src/test/ui/svh/svh-change-significant-cfg.rs
[ui] src/test/ui/svh/svh-change-trait-bound.rs
[ui] src/test/ui/svh/svh-change-type-arg.rs
[ui] src/test/ui/svh/svh-change-type-ret.rs
[ui] src/test/ui/svh/svh-change-type-static.rs
[ui] src/test/ui/svh/svh-use-trait.rs
test result: FAILED. 12915 passed; 12 failed; 100 ignored; 0 measured; 0 filtered out; finished in 71.41s
Some tests failed in compiletest suite=ui mode=ui host=x86_64-unknown-linux-gnu target=x86_64-unknown-linux-gnu
Build completed unsuccessfully in 0:01:58
</code>
</pre>
</details>
- I could not resolve the extra tasks about `create_rmeta_file` and `create_compressed_metadata_file` for my lack of ability.
Adding the option to control from rustc CLI
if the resulted ".o" bitcode module files are with
thinLTO info or regular LTO info.
Allows using "-lto-embed-bitcode=optimized" during linkage
correctly.
Signed-off-by: Ziv Dunkelman <ziv.dunkelman@nextsilicon.com>
To generate a function coverage we need at least one coverage counter,
so a coverage from unreachable blocks is retained only when some live
counters remain.
The previous implementation incorrectly retained unreachable coverage,
because it didn't account for the fact that those live counters can
belong to another function due to inlining.
