rust/library
León Orell Valerian Liehr 35ea48d588
Rollup merge of #118833 - Urgau:lint_function_pointer_comparisons, r=cjgillot
Add lint against function pointer comparisons

This is kind of a follow-up to https://github.com/rust-lang/rust/pull/117758 where we added a lint against wide pointer comparisons for being ambiguous and unreliable; well function pointer comparisons are also unreliable. We should IMO follow a similar logic and warn people about it.

-----

## `unpredictable_function_pointer_comparisons`

*warn-by-default*

The `unpredictable_function_pointer_comparisons` lint checks comparison of function pointer as the operands.

### Example

```rust
fn foo() {}
let a = foo as fn();

let _ = a == foo;
```

### Explanation

Function pointers comparisons do not produce meaningful result since they are never guaranteed to be unique and could vary between different code generation units. Furthermore different function could have the same address after being merged together.

----

This PR also uplift the very similar `clippy::fn_address_comparisons` lint, which only linted on if one of the operand was an `ty::FnDef` while this PR lints proposes to lint on all `ty::FnPtr` and `ty::FnDef`.

```@rustbot``` labels +I-lang-nominated

~~Edit: Blocked on https://github.com/rust-lang/libs-team/issues/323 being accepted and it's follow-up pr~~
2024-12-05 07:29:53 +01:00
..
alloc Use c"lit" for CStrings without unwrap 2024-12-02 18:16:36 +00:00
backtrace@230570f2da Try latest backtrace 2024-08-29 12:13:19 -07:00
core Rollup merge of #118833 - Urgau:lint_function_pointer_comparisons, r=cjgillot 2024-12-05 07:29:53 +01:00
panic_abort step cfg(bootstrap) 2024-07-28 14:46:29 -04:00
panic_unwind Rollup merge of #133622 - mkroening:exception-blog, r=cuviper 2024-12-01 08:15:24 +01:00
portable-simd move strict provenance lints to new feature gate, remove old feature gates 2024-10-21 15:22:17 +01:00
proc_macro rustc_allow_const_fn_unstable is not used in proc_macro 2024-11-30 11:55:58 +01:00
profiler_builtins Auto merge of #133369 - Zalathar:profiler-builtins-no-core, r=jieyouxu 2024-11-27 10:19:38 +00:00
rtstartup Let InstCombine remove Clone shims inside Clone shims 2024-07-25 15:14:42 -04:00
rustc-std-workspace-alloc Replace libstd, libcore, liballoc in line comments. 2022-12-30 14:00:42 +01:00
rustc-std-workspace-core update rustc-std-workspace crates 2024-11-04 07:45:15 +01:00
rustc-std-workspace-std
std Auto merge of #133818 - matthiaskrgr:rollup-iav1wq7, r=matthiaskrgr 2024-12-04 00:47:09 +00:00
stdarch@e5e00aab0a Bump stdarch to the latest master 2024-11-18 18:52:27 +01:00
sysroot Make profiler_builtins an optional dependency of sysroot, not std 2024-10-17 22:08:36 +11:00
test Update thread spawn hooks. 2024-11-19 18:54:20 +01:00
unwind update cfgs 2024-11-27 15:14:54 +00:00
windows_targets Win: Add dbghelp to the list of import libraries 2024-09-06 21:21:49 +00:00
Cargo.lock Rollup merge of #133515 - SteveLauC:fix/hurd, r=ChrisDenton 2024-12-01 08:15:22 +01:00
Cargo.toml Auto merge of #129063 - the8472:cold-opt-size, r=Amanieu 2024-09-02 00:58:50 +00:00