[ ] Reduce the issue to a minimal, self-contained, reproducible test case.
Avoid dependencies to Mathlib or Batteries.
Description
When running our lean-mlir tool, I found a testcase that was close to impossible to reduce. My code seems to finish the tactic evaluation, but hangs in the kernel. set_option debug.skipKernelTC true allows lean to terminate.
git clone git@github.com:opencompl/lean-mlir.git
cd lean-mlir
git checkout lean-deadlock
lake exe cache get
lake build
lake build SSA.Projects.InstCombine.tests.LLVM.gaddhmaskhnegtobias
Prerequisites
Please put an X between the brackets as you perform the following steps:
Description
When running our lean-mlir tool, I found a testcase that was close to impossible to reduce. My code seems to finish the tactic evaluation, but hangs in the kernel.
set_option debug.skipKernelTC true
allows lean to terminate.The stacktrace I obtain is:
The bug first appeared in the lean nightly 2024-10-19 (https://github.com/leanprover/lean4-nightly/releases/tag/nightly-2024-10-19). A potential guess is that https://github.com/leanprover/lean4/pull/5763 might potentially have introduced or exposed the bug in our particular setup.
The test case can be reproduced in this file:
https://github.com/opencompl/lean-mlir/blob/cc021f606793e86e8dcd469e21d365233fc16030/SSA/Projects/InstCombine/tests/LLVM/gaddhmaskhnegtobias.lean#L24
Steps to Reproduce
Observe the last command to hang.
Expected
Lean should not hang
Versions
Lean 4.12.0-nightly-2024-10-30 Target: arm64-apple-darwin23.6.0 macOS
Impact
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