Stop using old version of syn in rustc-workspace-hack

None of the tools seem to need syn 0.15.35, so we can just build syn
1.0.

This was causing an issue with clippy's `compile-test` program: since
multiple versions of `syn` would exist in the build directory, we would
non-deterministically pick one based on filesystem iteration order. If
the pre-1.0 version of `syn` was picked, a strange build error would
occur (see
https://github.com/rust-lang/rust/pull/73594#issuecomment-647671463)

To prevent this kind of issue from happening again, we now panic if we
find multiple versions of a crate in the build directly, instead of
silently picking the first version we find.
This commit is contained in:
Aaron Hill 2020-06-22 13:29:04 -04:00
parent 922ff8e485
commit e11b873c70

View File

@ -49,7 +49,9 @@ fn third_party_crates() -> String {
if let Some(name) = path.file_name().and_then(OsStr::to_str) {
for dep in CRATES {
if name.starts_with(&format!("lib{}-", dep)) && name.ends_with(".rlib") {
crates.entry(dep).or_insert(path);
if let Some(old) = crates.insert(dep, path.clone()) {
panic!("Found multiple rlibs for crate `{}`: `{:?}` and `{:?}", dep, old, path);
}
break;
}
}