Avoid leaking the query-job collection warning into the panic query stack#157351
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xmakro wants to merge 2 commits into
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Avoid leaking the query-job collection warning into the panic query stack#157351xmakro wants to merge 2 commits into
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`collect_active_query_jobs` with `CollectActiveJobsKind::PartialAllowed` is only used to print the query stack when the compiler panics. It intentionally skips any query state shard whose lock it cannot take without waiting, since a complete job map is not needed for that. Under the parallel front-end another thread can still hold a shard lock while the panic is being reported, so the skip happens nondeterministically and the `warn!` was printed into the panic output. Because warnings are shown by default, this leaked a "Failed to collect active jobs" line into the diagnostics of panicking compilations and made their output unstable. Lower the message to `debug!` so it stays available with `RUSTC_LOG` but no longer pollutes the default output.
…nt-end This test was marked `ignore-parallel-frontend` because the panic-time query stack collection could nondeterministically print a "Failed to collect active jobs" warning. With that warning lowered to `debug!` the ICE output is stable across runs, so remove the directive and rebless the stderr. The only stderr change is line numbers shifting by one after the directive line is removed.
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Part of #154314.
When the compiler panics it prints the active query stack. That collection runs with
CollectActiveJobsKind::PartialAllowed, which deliberately skips any query state shard whose lock it cannot take without waiting, since a complete job map is not needed just to print a stack.Under the parallel front-end another thread can still hold a shard lock while the panic is being reported, so a shard is skipped nondeterministically and a
warn!("Failed to collect active jobs ...")was printed. Because warnings are shown by default (the defaultRUSTC_LOGfilter isWARN), this leaked an extra line into the diagnostics of panicking compilations and made their output differ run to run. The panicking thread's own query chain is always collectible (a query does not hold its shard lock while it runs), so the printed stack itself is unaffected; only the spurious warning varied.A skipped shard is expected and tolerated on this path, so
warn!was the wrong level for it to begin with. This lowers the message todebug!so it stays available withRUSTC_LOGbut no longer pollutes the default output, and re-enables the one ui test that was disabled because of it.