Use `as_deref` in compiler (but only where it makes sense)
This simplifies some code :3
(there are some changes that are not exacly `as_deref`, but more like "clever `Option`/`Result` method use")
Previously if the parent was not in the table, and there was nothing to inherit from, the child's private visibility was used, but that's not correct - the parent may have a larger visibility so we should set it to at least the parent's private visibility.
That parent's private visibility is also inserted into the table for caching, so it's not recalculated later if used again.
By using `display: flex`, we still get the never-wrapping layout with
`#crate-search-div` maxing out and truncating its text. The title itself
winds up always filling its parent, but since `#crate-search` doesn't have
`flex-grow` set, it won't fill available space.
Optimizations removed in the previous commit required this function to behave incorrectly, but now those optimizations are gone so we can fix the bug.
Fixes https://github.com/rust-lang/rust/issues/104249
First, they require eagerly calculating private visibility (current normal module), which is somewhat expensive.
Private visibilities are also lost once calculated, instead of being cached in the table.
Second, I cannot prove that the optimizations are correct.
Maybe they can be partially reinstated in the future in cases when it's cheap and provably correct to do them.
They will also probably be merged into `fn update` in that case.
Partially fixes https://github.com/rust-lang/rust/issues/104249
Fixes https://github.com/rust-lang/rust/issues/104539
copy doc output files by format
This pr provides copying doc outputs by checking output format without removing output directory on each trigger.
Resolves#103785
Fix hang in where-clause suggestion with `predicate_can_apply`
Using `predicate_may_hold` during error reporting causes an evaluation overflow, which (because we use `evaluate_obligation_no_overflow`) then causes the predicate to need to be re-evaluated locally, which results in a hang.
... but since the "add a where clause" suggestion is best-effort, just throw any overflow errors. No need for 100% accuracy.
r? `@lcnr` who has been thinking about overflows... Let me know if you want more context about this issue, and as always, feel free to reassign.
Fixes#104225
optimize field ordering by grouping m*2^n-sized fields with equivalently aligned ones
```rust
use std::ptr::addr_of;
use std::mem;
struct Foo {
word: u32,
byte: u8,
ary: [u8; 4]
}
fn main() {
let foo: Foo = unsafe { mem::zeroed() };
println!("base: {:p}\nword: {:p}\nbyte: {:p}\nary: {:p}", &foo, addr_of!(foo.word), addr_of!(foo.byte), addr_of!(foo.ary));
}
```
prints
```
base: 0x7fffc1a8a668
word: 0x7fffc1a8a668
byte: 0x7fffc1a8a66c
ary: 0x7fffc1a8a66d
```
I.e. the `u8` in the middle causes the array to sit at an odd offset, which might prevent optimizations, especially on architectures where unaligned loads are costly.
Note that this will make field ordering niche-dependent, i.e. a `Bar<T>` with `T=char` and `T=u32` may result in different field order, this may break some code that makes invalid assumptions about `repr(Rust)` types.
