I got a notification that the flate2 project's coverage build is failing and has the error message:

Step #5: warning: /workspace/out/coverage/dumps/fuzz_gz_roundtrip.16218861006045500770_0.profraw: Unsupported instrumentation profile format version
Step #5: error: No profiles could be merged.

AFAIK nothing about flate2 itself has changed, but the most recent change I can think of is that the Rust compiler upgraded to LLVM 13 over the weekend. I suspect that the new LLVM version may have updated something about coverage instrumentation?