Ensure RPITITs are created before def-id freezing

[compiler-errors]

From the test:

// `ty::Error` in a trait ref will silence any missing item errors, but will also
// prevent the `associated_items` query from being called before def ids are frozen.

Essentially, the code that checks that impls have all their items (check_impl_items_against_trait) is also (implicitly) responsible for fetching the associated_items query before, but since we early return here:

rust/compiler/rustc_hir_analysis/src/check/check.rs

Lines 732 to 737 in c2901f5

	// If the trait reference itself is erroneous (so the compilation is going
	// to fail), skip checking the items here -- the `impl_item` table in `tcx`
	// isn't populated for such impls.
	if trait_ref.references_error() {
	return;
	}

...that means that this never happens for trait refs that reference errors.

Fixes #122518
r? oli-obk

[oli-obk]

@bors r+ rollup

[bors]

📌 Commit 571f945 has been approved by oli-obk

It is now in the queue for this repository.