While this definitely helps sometimes (particularly for trivial closures), it's also a pessimization sometimes, so it's better to leave this to (hypothetical) future LLVM improvements instead of forcing this on everyone.
I think it's better for the advice to be that sometimes you need to unroll manually than you sometimes need to not-unroll manually (like #64545).
Rollup of 9 pull requests
Successful merges:
- #63907 (Add explanation to type mismatch involving type params and assoc types)
- #64615 (rustbuild: Turn down compression on exe installers)
- #64617 (rustbuild: Turn down compression on msi installers)
- #64618 (rustbuild: Improve output of `dist` step)
- #64619 (Fixes#63962. Hint about missing tuple parentheses in patterns)
- #64634 (Update to LLVM 9.0.0)
- #64635 (Allow using fn pointers in const fn with unleash miri)
- #64660 (unify errors for tuple/struct variants)
- #64664 (fully remove AstBuilder)
Failed merges:
r? @ghost
Allow using fn pointers in const fn with unleash miri
This allows using function pointers in const fns when `-Zunleash-the-miri-within-you` is enabled.
If the call to the `const fn` happens in a `const`-context, the function pointer is required to point to a `const fn`:
```rust
fn non_const_fn() -> i32 { 42 }
const fn const_fn() -> i32 { 42 }
const fn foo(x: fn() -> i32) -> i32 { x() }
let x: i32 = foo(non_const_fn_ptr); // OK
let y: i32 = foo(const_fn_ptr); // OK
const X: i32 = foo(non_const_fn_ptr); // ERROR: `non_const_fn` is not `const fn`
const Y: i32 = foo(const_fn_ptr); // OK
```
r? @oli-obk
rustbuild: Improve output of `dist` step
* Pass `/Q` to `iscc` on Windows to supress the thousands of lines of
output about compressing documentation.
* Print out what's happening before long steps
* Use `timeit` to print out timing information for long-running
installer assemblies.
* Try to scope output of `Dist ...` to not also encompass actual build steps
rustbuild: Turn down compression on msi installers
This is the same as #64615 except applied to our MSI installers. The
same fix is applied effectively bringing these installers in line with
the gz tarball installers, which are about 3x faster to produce locally
and likely much faster to produce on CI.
rustbuild: Turn down compression on exe installers
The Windows dist builders are the slowest builders right now, and the
distribution phase of them is enormously slow clocking in at around 20
minutes to build all the related installers. This commit starts to
optimize these by turning down the compression level in the `exe`
installers. These aren't super heavily used so there's no great need for
them to be so ultra-compressed, so let's dial back the compression
parameters to get closer to the rest of our xz archives. This brings the
installer in line with the gz tarball installer locally, and also brings
the compression settings on par with the rest of our xz installers.
