Borrow checker error on nightly even when the type is 'static #106332
Description
Compiling the binstalk from cargo-bins/cargo-binstall#646 failed on nightly due to lifetime error while it works on stable.
The code in question looks like this and is in taken from crates/binstalk/src/fetchers/gh_crate_meta.rs
pub struct GhCrateMeta {
client: Client,
data: Arc<Data>,
target_data: Arc<TargetData>,
resolution: OnceCell<(Url, PkgFmt)>,
}
type FindTaskRes = Result<Option<(Url, PkgFmt)>, BinstallError>;
impl GhCrateMeta {
fn launch_baseline_find_tasks<'a>(
&'a self,
pkg_fmt: PkgFmt,
pkg_url: &'a str,
repo: Option<&'a str>,
) -> impl Iterator<Item = impl Future<Output = FindTaskRes> + 'static> + 'a {
todo!()
}
fn find(self: Arc<Self>) -> AutoAbortJoinHandle<Result<bool, BinstallError>> {
AutoAbortJoinHandle::spawn(async move {
// ...
let mut handles = FuturesUnordered::new();
// Iterate over pkg_urls to avoid String::clone.
for pkg_url in pkg_urls {
// Clone iter pkg_fmts to ensure all pkg_fmts is
// iterated over for each pkg_url, which is
// basically cartesian product.
// |
for pkg_fmt in pkg_fmts.clone() {
handles.extend(this.launch_baseline_find_tasks(pkg_fmt, &pkg_url, repo));
}
}
todo!()
})
}On nightly, this failed with:
error[E0597]: `pkg_url` does not live long enough
--> crates/binstalk/src/fetchers/gh_crate_meta.rs:147:77
|
147 | handles.extend(this.launch_baseline_find_tasks(pkg_fmt, &pkg_url, repo));
| ^^^^^^^^ borrowed value
does not live long enough
148 | }
149 | }
| - `pkg_url` dropped here while still borrowed
...
160 | })
| - borrow might be used here, when `handles` is dropped and runs the `Drop` code for type `Fu
turesUnordered`
|
= note: values in a scope are dropped in the opposite order they are defined
For more information about this error, try `rustc --explain E0597`.
error: could not compile `binstalk` due to previous error
warning: build failed, waiting for other jobs to finish...
error: could not compile `binstalk` due to previous error
Meta
rustc +nightly --version --verbose:
rustc 1.68.0-nightly (ce85c9857 2022-12-30)
binary: rustc
commit-hash: ce85c98575e3016cf2007d90a85be321e592aa96
commit-date: 2022-12-30
host: aarch64-apple-darwin
release: 1.68.0-nightly
LLVM version: 15.0.6