diff --git a/compiler/rustc_metadata/src/locator.rs b/compiler/rustc_metadata/src/locator.rs index 112954eca0df..f0a898d678ca 100644 --- a/compiler/rustc_metadata/src/locator.rs +++ b/compiler/rustc_metadata/src/locator.rs @@ -427,12 +427,21 @@ impl<'a> CrateLocator<'a> { let (rlibs, rmetas, dylibs) = candidates.entry(hash.to_string()).or_default(); - let path = - try_canonicalize(&spf.path).unwrap_or_else(|_| spf.path.to_path_buf()); - if seen_paths.contains(&path) { - continue; - }; - seen_paths.insert(path.clone()); + { + // As a perforamnce optimisation we canonicalize the path and skip + // ones we've already seeen. This allows us to ignore crates + // we know are exactual equal to ones we've already found. + // Going to the same crate through different symlinks does not change the result. + let path = try_canonicalize(&spf.path) + .unwrap_or_else(|_| spf.path.to_path_buf()); + if seen_paths.contains(&path) { + continue; + }; + seen_paths.insert(path); + } + // Use the original path (potentially with unresolved symlinks), + // filesystem code should not care, but this is nicer for diagnostics. + let path = spf.path.to_path_buf(); match kind { CrateFlavor::Rlib => rlibs.insert(path, search_path.kind), CrateFlavor::Rmeta => rmetas.insert(path, search_path.kind),