It can be useful to do some computation in `assert!` format arguments, in order to get better error messages. For example:
```rust
assert!(
some_condition,
"The state is invalid. Details: {}",
expensive_call_to_get_debugging_info(),
);
```
It seems like `assert!` only evaluates the format arguments if the assertion fails, which is useful but doesn't appear to be documented anywhere. This PR documents the behavior and adds some tests.
Ensures `make` tests run under /bin/dash (if available), like CI, and fixes a Makefile
Note: This cherrypicks #81688 (`@pnkfelix)`
Updates `tools.mk` to explicitly require `SHELL := /bin/dash`, since CI uses `dash` but other environments (including developer local machines) may default to `bash`.
Replaces bash-specific shell command in one Makefile with a dash-compatible alternative, and re-enables the affected Makefile test.
Removes apparently redundant definition of `UNAME`.
Also see: [zulip discussion thread](https://rust-lang.zulipchat.com/#narrow/stream/131828-t-compiler/topic/how.20to.20run.2Fbless.20src.2Ftest.2Frun-make-fulldeps.2Fcoverage.20.3F)
r? `@pnkfelix`
FYI: `@wesleywiser` `@tmandry`
Along the way, we also implement a handful of diagnostics improvements
and fixes, particularly with respect to the special handling of `||` in
place of `|` and when there are leading verts in function params, which
don't allow top-level or-patterns anyway.
This does not suggest adding such a function to the public API. This is
just for the purpose of avoiding duplicate code. Many array methods
already contained the same kind of code and there are still many array
related methods to come (e.g. `Iterator::{chunks, map_windows, next_n,
...}`) which all basically need this functionality. Writing custom
`unsafe` code for each of those seems not like a good idea.
32-bit ARM: Emit `lr` instead of `r14` when specified as an `asm!` output register.
On 32-bit ARM platforms, the register `r14` has the alias `lr`. When used as an output register in `asm!`, rustc canonicalizes the name to `r14`. LLVM only knows the register by the name `lr`, and rejects it. This changes rustc's LLVM code generation to output `lr` instead.
closes#82052
r? ``@nagisa``
Remove unnecessary `Option` in `default_doc`
Previously, there were two different ways to encode the same info: `None` or
`Some(&[])`. Now there is only one way, `&[]`.
const_generics: Fix incorrect ty::ParamEnv::empty() usage
Fixes#80561
Not sure if I should keep the `debug!(..)`s or not but its the second time I've needed them so they sure seem useful lol
cc ``@lcnr``
r? ``@oli-obk``
