Incompatible with nightly-2021-09-26: unknown pass name 'sancov'

[dtolnay]

I noticed that serde_json's fuzz target does not build using the most recent nightly. It's been working for a long time so this is a recent breakage.

Repro:

$ cargo fuzz init
$ cargo +nightly-2021-09-25 fuzz build  # works
$ cargo +nightly-2021-09-26 fuzz build

error: failed to run LLVM passes: unknown pass name 'sancov'

error: could not compile `once_cell` due to previous error
warning: build failed, waiting for other jobs to finish...
error: build failed
Error: failed to build fuzz script: "cargo" "build" "--manifest-path" "fuzz/Cargo.toml" "--target" "x86_64-unknown-linux-gnu" "--release" "--bins"

The upstream commit range is rust-lang/rust@7342213...addb4da.

[dtolnay]

• Enable new pass manager with LLVM 13 rust-lang/rust#88243 looks like the most relevant change.

[nagisa]

There are two straightforward approaches to fixing this but either approach will also prevent any operation with versions of rustc without newpm. It's probably fine though?

…

On Sun, 26 Sep 2021, 07:13 David Tolnay, ***@***.***> wrote: - rust-lang/rust#88243 <rust-lang/rust#88243> looks like the most relevant change. — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#276 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAFFZUUESHGNBJNDDFQNEDLUD2MXFANCNFSM5EYKN6FQ> . Triage notifications on the go with GitHub Mobile for iOS <https://apps.apple.com/app/apple-store/id1477376905?ct=notification-email&mt=8&pt=524675> or Android <https://play.google.com/store/apps/details?id=com.github.android&referrer=utm_campaign%3Dnotification-email%26utm_medium%3Demail%26utm_source%3Dgithub>.