This includes everything necessary for promoting borrows of constant rvalues to `'static`.
That is, `&expr` will have the type `&'static T` if `const T: &'static T = &expr;` is valid.
There is a small exception, dereferences of raw pointers, as they misbehave.
They still "work" in constants as I didn't want to break legitimate uses (are there any?).
The qualification done here can be expanded to allow simple CTFE via `const fn`.
Nonetheless, as this commit demonstrates, the previous commits was a [breaking-change].
In practice, breakage is focused on functions of this form:
```rust
fn foo(..., object: Box<FnMut()>)
````
where `FnMut()` could be any trait object type. The older scheme defaulted objects in argument
position so that they were bounded by a fresh lifetime:
```rust
fn foo<'a>(..., object: Box<FnMut()+'a>)
```
This meant that the object could contain borrowed data. The newer
scheme defaults to a lifetime bound of `'static`:
```rust
fn foo(..., object: Box<FnMut()+'static>)
```
This means that the object cannot contain borrowed data. In some cases, the best fix
is to stop using `Box`:
```rust
fn foo(..., object: &mut FnMut())
```
but another option is to write an explicit annotation for the `'a`
lifetime that used to be implicit. Both fixes are demonstrated in
this commit.
The test "signal_reported_right" send a signal `1` to `/bin/sh`, and check
the status code to check if the signal is reported right.
Under OpenBSD, the signal `1` (`SIGHUP`) is catched by `/bin/sh`,
resulting the test failed.
Use the uncatchable signal `9` (`SIGKILL`) for test.
This redux of CONTRIBUTING.md adds in more information, including
subsuming both compliment-bugreport.md and Note-development-policy
in the wiki.
I only glanced at the broad TOC of Note-development-policy, and did
not use the text as the basis for the re-write. This will then address
the last outstanding part of #5831.
- We shouldn't be using `check_name` here at all
- `contains_name(ref_slice(foo), bar)` is redundant, `contains_name` just iterates over its first arg and calls `check_name`
- match would be better than a bunch of ifs
When matching against strings/slices, we call the comparison function
for strings, which takes two string slices by value. The slices are
passed in memory, and currently we just pass in a pointer to the
original slice. That can cause misoptimizations because we emit a call
to llvm.lifetime.end for all by-value arguments at the end of a
function, which in this case marks the original slice as dead.
So we need to properly create copies of the slices to pass them to the
comparison function.
Fixes#22008
