Check lifetime param count in `collect_trait_impl_trait_tys`
We checked the type and const generics count, but not the lifetimes, which were handled in a different function.
Fixes#105154
rustdoc: clean up help and settings button CSS
The old version of this code specified a bunch of different numbers that had to line up just right to get the size it wanted. This version uses flexbox centering, specifies the font size, and lets the browser figure out the rest of the layout automatically.
Preview: http://notriddle.com/notriddle-rustdoc-demos/flexbox-help-settings-buttons/test_dingus/
sparc-struct-abi: work around new tail-call optimization
Upstream LLVM change https://reviews.llvm.org/D138741 introduced some new tail-call smarts for SPARC which broke some of the checks in this test. Rather than adjust the test expectations, we add an extra no-args function that can get tail-called or not without hurting the needs of the test.
r? ``@nikic``
Adjust inlining attributes around panic_immediate_abort
The goal of `panic_immediate_abort` is to permit the panic runtime and formatting code paths to be optimized away. But while poking through some disassembly of a small program compiled with that option, I found that was not the case. Enabling LTO did address that specific issue, but enabling LTO is a steep price to pay for this feature doing its job.
This PR fixes that, by tweaking two things:
* All the slice indexing functions that we `const_eval_select` on get `#[inline]`. `objdump -dC` told me that originally some `_ct` functions could end up in an executable. I won't pretend to understand what's going on there.
* Normalize attributes across all `panic!` wrappers: use `inline(never) + cold` normally, and `inline` when `panic_immediate_abort` is enabled.
But also, with LTO and `panic_immediate_abort` enabled, this patch knocks ~709 kB out of the `.text` segment of `librustc_driver.so`. That is slightly surprising to me, my best theory is that this shifts some inlining earlier in compilation, enabling some subsequent optimizations. The size improvement of `librustc_driver.so` with `panic_immediate_abort` due to this patch is greater with LTO than without LTO, which I suppose backs up this theory.
I do not know how to test this. I would quite like to, because I think what this is solving was an accidental regression. This only works with `-Zbuild-std` which is a cargo flag, and thus can't be used in a rustc codegen test.
r? `@thomcc`
---
I do not seriously think anyone is going to use a compiler built with `panic_immediate_abort`, but I wanted a big complicated Rust program to try this out on, and the compiler is such.
The StableOrd trait can be used to mark types as having a stable
sort order across compilation sessions. Collections that sort their
items in a stable way can safely implement HashStable by
hashing items in sort order.
Reorganizing `stacked_borrows` in anticipation of a different model
These commits reorganize all the code inside the former `stacked_borrows` module and extract the part that really is specific to Stacked Borrows inside the `borrow_tracker/stacked_borrows` submodule.
Everything not specific to SB is put in `borrow_tracker/mod.rs`.
This is so that the future Tree Borrows model can be later added as a second submodule and reuse all the contents of `borrow_tracker/mod.rs`.
This reorganization is accompanied by renamings, mostly from "stacked borrows" to "borrow tracking".
