…=jackh726

Harmonize using root or leaf obligation in trait error reporting

When rust-lang#121826 changed the error reporting to use root obligation and not the leafmost obligation, it didn't actually make sure that all the other diagnostics helper functions used the right obligation.

Specifically, when reporting similar impl candidates we are looking for impls of the root obligation, but trying to match them against the trait ref of the leaf obligation.

This does a few other miscellaneous changes. There's a lot more clean-up that could be done here, but working with this code is really grief-inducing due to how messy it has become over the years. Someone really needs to show it love. 😓

r? `@estebank`

Fixes rust-lang#126129

…=jackh726

Harmonize using root or leaf obligation in trait error reporting

When rust-lang#121826 changed the error reporting to use root obligation and not the leafmost obligation, it didn't actually make sure that all the other diagnostics helper functions used the right obligation.

Specifically, when reporting similar impl candidates we are looking for impls of the root obligation, but trying to match them against the trait ref of the leaf obligation.

This does a few other miscellaneous changes. There's a lot more clean-up that could be done here, but working with this code is really grief-inducing due to how messy it has become over the years. Someone really needs to show it love. 😓

r? `@estebank`

Fixes rust-lang#126129

…kingjubilee

Rollup of 11 pull requests

Successful merges:

 - rust-lang#125165 (Migrate `run-make/pgo-branch-weights` to `rmake`)
 - rust-lang#125674 (Rewrite `symlinked-extern`, `symlinked-rlib` and `symlinked-libraries` `run-make` tests in `rmake.rs` format)
 - rust-lang#125688 (Walk into alias-eq nested goals even if normalization fails)
 - rust-lang#126142 (Harmonize using root or leaf obligation in trait error reporting)
 - rust-lang#126303 (Urls to docs in rust_hir)
 - rust-lang#126328 (Add Option::is_none_or)
 - rust-lang#126337 (Add test for walking order dependent opaque type behaviour)
 - rust-lang#126351 (std::unix::fs::link using direct linkat call for Solaris.)
 - rust-lang#126353 (Move `MatchAgainstFreshVars` to old solver)
 - rust-lang#126356 (docs(rustc): Improve discoverable of Cargo docs)
 - rust-lang#126362 (Make `try_from_target_usize` method public)

r? `@ghost`
`@rustbot` modify labels: rollup

…kingjubilee

Rollup of 10 pull requests

Successful merges:

 - rust-lang#125674 (Rewrite `symlinked-extern`, `symlinked-rlib` and `symlinked-libraries` `run-make` tests in `rmake.rs` format)
 - rust-lang#125688 (Walk into alias-eq nested goals even if normalization fails)
 - rust-lang#126142 (Harmonize using root or leaf obligation in trait error reporting)
 - rust-lang#126303 (Urls to docs in rust_hir)
 - rust-lang#126328 (Add Option::is_none_or)
 - rust-lang#126337 (Add test for walking order dependent opaque type behaviour)
 - rust-lang#126353 (Move `MatchAgainstFreshVars` to old solver)
 - rust-lang#126356 (docs(rustc): Improve discoverable of Cargo docs)
 - rust-lang#126358 (safe transmute: support `Single` enums)
 - rust-lang#126362 (Make `try_from_target_usize` method public)

r? `@ghost`
`@rustbot` modify labels: rollup

Rollup merge of rust-lang#126142 - compiler-errors:trait-ref-split, r=jackh726

Harmonize using root or leaf obligation in trait error reporting

When rust-lang#121826 changed the error reporting to use root obligation and not the leafmost obligation, it didn't actually make sure that all the other diagnostics helper functions used the right obligation.

Specifically, when reporting similar impl candidates we are looking for impls of the root obligation, but trying to match them against the trait ref of the leaf obligation.

This does a few other miscellaneous changes. There's a lot more clean-up that could be done here, but working with this code is really grief-inducing due to how messy it has become over the years. Someone really needs to show it love. 😓

r? ``@estebank``

Fixes rust-lang#126129