epoll: handle edge case for epoll_ctl
There is a test case that revealed that our implementation differs from the real system:
- Set up an epoll watching the FD
- Call epoll_wait
- Set up another epoll watching the same FD
- Call epoll_wait on the first epoll. Nothing should be reported!
This happened because, in ``epoll_ctl``, we used ``check_and_update_readiness``, which is a function that would return notification for all epoll file description that registered a particular file description. But we shouldn't do that because no notification should be returned if there is no I/O activity between two ``epoll_wait`` (every first ``epoll_wait`` that happens after ``epoll_ctl`` is an exception, we should return notification that reflects the readiness of file description).
r? `@oli-obk`
epoll: Add a EINVAL case
In ``epoll_ctl`` documentation, it is mentioned that:
> EINVAL epfd is not an epoll file descriptor, or fd is the same as epfd, or the requested operation op is not supported by this interface.
So I added this EINVAL case for ``epfd == fd`` in ``epoll_ctl``
Avoid extra copy by using `retain_mut` and moving the deletion into the closure
Fixes the FIXME introduced in #3833. Thanks to `@dmitrii-ubskii` for the idea 🙂
Fix a misleading comment in `tests/pass/tree_borrows/tree-borrows.rs`
The original comment is somewhat misleading.
Since we don't add a protector for `x` here, `f` should be allowed to deallocate `x`.
Make Tree Borrows Provenance GC no longer produce stack overflows
Most functions operating on Tree Borrows' trees are carefully written to not cause stack overflows due to too much recursion. The one exception is [`Tree::keep_only_needed`](94f5588faf/src/borrow_tracker/tree_borrows/tree.rs (L724)), which just uses regular recursion.
This function is part of the provenance GC, so it is called regularly for every allocation in the program.
Tests show that this is a problem in practice. For example, the test `fill::horizontal_line` in crate `tiny-skia` (version 0.11.4) is such a test.
This PR changes this, this test no now longer crashes. Instead, it succeeds (after a _long_ time).
epoll test: avoid some subtly dangling pointers
Turns out `let data = MaybeUninit::<u64>::uninit().as_ptr();` is a dangling pointer, the memory gets freed at the end of that line. For these cases we don't care as we don't actually access the pointer, but let's not do such subtle things.
Implement SHA256 SIMD intrinsics on x86
Disclaimer: this is my first contribution to `miri`'s code. It's quite possible I'm missing something. This code works but may not be the cleanest/best possible.
It'd be useful to be able to verify code implementing SHA256 using SIMD since such code is a bit more complicated and at some points requires use of pointers. Until now `miri` didn't support x86 SHA256 intrinsics. This commit implements them.
It'd be useful to be able to verify code implementing SHA256 using SIMD
since such code is a bit more complicated and at some points requires
use of pointers. Until now `miri` didn't support x86 SHA256 intrinsics.
This commit implements them.
Added "copy" to Debug fmt for copy operands
In MIR's debug mode (--emit mir) the printing for Operands is slightly inconsistent.
The RValues - values on the right side of an Assign - are usually printed with their Operand when they are Places.
Example:
_2 = move _3
But for arguments, the operand is omitted.
_2 = _1
I propose a change be made, to display the place with the operand.
_2 = copy _1
Move and copy have different semantics, meaning this difference is important and helpful to the user. It also adds consistency to the pretty printing.
-- EDIT --
Consider this example Rust program and its MIR output with the **updated pretty printer.**
This was generated with the arguments --emit mir --crate-type lib -Zmir-opt-level=0 (Otherwise, it's optimised away since it's a junk program).
```rust
fn main(foo: i32) {
let v = 10;
if v == 20 {
foo;
}
else {
v;
}
}
```
```MIR
// WARNING: This output format is intended for human consumers only
// and is subject to change without notice. Knock yourself out.
fn main(_1: i32) -> () {
debug foo => _1;
let mut _0: ();
let _2: i32;
let mut _3: bool;
let mut _4: i32;
let _5: i32;
let _6: i32;
scope 1 {
debug v => _2;
}
bb0: {
StorageLive(_2);
_2 = const 10_i32;
StorageLive(_3);
StorageLive(_4);
_4 = copy _2;
_3 = Eq(move _4, const 20_i32);
switchInt(move _3) -> [0: bb2, otherwise: bb1];
}
bb1: {
StorageDead(_4);
StorageLive(_5);
_5 = copy _1;
StorageDead(_5);
_0 = const ();
goto -> bb3;
}
bb2: {
StorageDead(_4);
StorageLive(_6);
_6 = copy _2;
StorageDead(_6);
_0 = const ();
goto -> bb3;
}
bb3: {
StorageDead(_3);
StorageDead(_2);
return;
}
}
```
In this example program, we can see that when we move a place, it is preceded by "move". e.g. ``` _3 = Eq(move _4, const 20_i32);```. However, when we copy a place such as ```_5 = _1;```, it is not preceded by the operand in the original printout. I propose to change the print to include the copy ```_5 = copy _1``` as in this example.
Regarding the arguments part. When I originally submitted this PR, I was under the impression this only affected the print for arguments to a function, but actually, it affects anything that uses a copy. This is preferable anyway with regard to consistency. The PR is about making ```copy``` explicit.
Prevent double panic in query system, improve diagnostics
I stumbled upon a double-panic in the query system while working on something else (#129102), which hid the real error cause for what I was debugging. This PR remedies that, so unwinding should be able to present more errors. It shouldn't really be relevant for code that doesn't ICE.
safe transmute: check lifetimes
Modifies `BikeshedIntrinsicFrom` to forbid lifetime extensions on references. This static check can be opted out of with the `Assume::lifetimes` flag.
Fixes#129097
Tracking Issue: https://github.com/rust-lang/rust/issues/99571
r? `@compiler-errors`
Delete debuginfo test suite infra for gdb without Rust support and lldb with Rust support
Implements https://github.com/rust-lang/rust/issues/128953
I also deleted all the `min-lldb-version: 310` comments, because the oldest compatible distro I can find is Ubuntu 16.04 which ships lldb 3.8, though of course the package that the Ubuntu maintainers put together for that is broken.
Rocky Linux 8 amusingly ships lldb 17, even though it has a similar glibc and kernel version.
This PR is multiple highly mechanical changes. Some of the commits were created by just running `sed`. You may find it easier to review each commit separately.
Switch to using the v2 resolver in most workspaces
Pinning the resolver to v1 was done in 5abff3753a ("Explicit set workspace.resolver ...") in order to suppress warnings. Since there is no specific reason not to use the new resolver and since it fixes issues, change to `resolver = "2"` everywhere except library.
Rollup of 7 pull requests
Successful merges:
- #127679 (Stabilize `raw_ref_op` (RFC 2582))
- #128084 (Suggest adding Result return type for associated method in E0277.)
- #128628 (When deduplicating unreachable blocks, erase the source information.)
- #128902 (doc: std::env::var: Returns None for names with '=' or NUL byte)
- #129048 (Update `crosstool-ng` for loongarch64)
- #129116 (Include a copy of `compiler-rt` source in the `download-ci-llvm` tarball)
- #129208 (Fix order of normalization and recursion in const folding.)
r? `@ghost`
`@rustbot` modify labels: rollup
Fix order of normalization and recursion in const folding.
Fixes#126831.
Without this patch, type normalization is not always idempotent, which leads to all sorts of bugs in places that assume that normalizing a normalized type does nothing.
Tracking issue: https://github.com/rust-lang/rust/issues/95174
r? BoxyUwU
Include a copy of `compiler-rt` source in the `download-ci-llvm` tarball
This will make it possible to experiment with allowing `download-ci-llvm` builds to build `library/profiler_builtins`, without needing to check out the `src/llvm-project` submodule.
By itself, this PR just adds the files to the tarball, but doesn't actually do anything with them. The idea is that once this is merged, it will then be much easier to proceed with work on the necessary bootstrap changes (using the real downloaded tarball), without having to rig up weird hacks to simulate downloading a modified tarball.
---
Adding these files to the compressed tarballs appears to increase its size by a negligible amount (<1 MB out of 400/800+ MB).
The uncompressed size is about 14 MB (out of 2+ GB for the whole tarball).
(The excluded test files would have been another 35 MB.)
