rustdoc link resolution is nondeterministic, depends on job number

[jonas-schievink]

rust-analyzer generates documentation by running cargo doc --all --no-deps in CI, but I've noticed that the resulting documentation doesn't have any clickable links, even to other workspace crates. Some investigation showed that I couldn't reproduce this behavior locally unless I pass -j1 to Cargo, which indicates that the behavior is nondeterministic.

In total, I've observed these 3 different results:

These were all generated from the same commit, rust-lang/rust-analyzer@761b127, using Rust 1.66.0. (the item is hir::Semantics::speculative_expand)

[jyn514]

Some investigation showed that I couldn't reproduce this behavior locally unless I pass -j1 to Cargo, which indicates that the behavior is nondeterministic.

If this is fixed by running fewer rustdoc processes in parallel, this is a cargo issue, not a rustdoc issue. Cargo needs to only run rustdoc on the crate once all its dependencies have been documented.

cc

rust/src/librustdoc/clean/types.rs

Lines 177 to 183 in c83553d

	// See if there's documentation generated into the local directory
	// WARNING: since rustdoc creates these directories as it generates documentation, this check is only accurate before rendering starts.
	// Make sure to call `location()` by that time.
	let local_location = dst.join(self.name(tcx).as_str());
	if local_location.is_dir() {
	return Local;
	}