https://github.com/charles-zablit created https://github.com/llvm/llvm-project/pull/213239
On Windows, when a test hits a timeout, we currently don't get a stacktrace. dotest solves this on POSIX: it registers a SIGTERM handler, so a killed test prints its stack. The handler does not run on Windows however because `faulthandler.register` doesn't exist there, and lit terminates the process instead of signalling it (no signals on Windows). This patch adds `faulthandler.dump_traceback_later()` with a default timeout value of 300s. That's longer than the longest test in CI (~150s) and does not kill the test. It simply dumps the stacktrace at a point where the test is very likely stuck. # Before ``` TIMEOUT: lldb-api :: types/TestFloatTypesExpr.py (2698 of 2698) ******************** TEST 'lldb-api :: types/TestFloatTypesExpr.py' FAILED ******************** Exit Code: 15 Timeout: Reached timeout of 900 seconds ``` There is no stacktrace. # After ``` Timeout (0:00:20)! Thread 0x00012fe8 (most recent call first): File ".../types/TestFloatTypesExpr.py", line 22 in test_float_type File ".../lldbsuite/test/lldbtest.py", line 2097 in test_method File ".../unittest/case.py", line 549 in _callTestMethod ... File ".../lldbsuite/test/dotest.py", line 1212 in run_suite ``` >From c9328894f9f598158357fee314aa89b06705f0eb Mon Sep 17 00:00:00 2001 From: Charles Zablit <[email protected]> Date: Fri, 31 Jul 2026 12:31:33 +0200 Subject: [PATCH] [lldb][Windows] Dump thread stacks before lit's timeout kills a test --- lldb/packages/Python/lldbsuite/test/dotest.py | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/lldb/packages/Python/lldbsuite/test/dotest.py b/lldb/packages/Python/lldbsuite/test/dotest.py index 604fb98b1e2e5..3c966dceb96c7 100644 --- a/lldb/packages/Python/lldbsuite/test/dotest.py +++ b/lldb/packages/Python/lldbsuite/test/dotest.py @@ -504,6 +504,19 @@ def registerFaulthandler(): if getattr(faulthandler, "register", None): faulthandler.register(signal.SIGTERM, chain=True) + if sys.platform != "win32": + return + + # lit kills a hung test with TerminateProcess on Windows, so the SIGTERM + # handler above never runs and a timeout is reported with no indication of + # where it hung. Dump every thread's stack while the process is still alive. + try: + secs = float(os.environ.get("LLDB_TEST_STACK_DUMP_SECS", 300)) + except ValueError: + secs = 300 + if secs > 0: + faulthandler.dump_traceback_later(secs, exit=False) + def setupSysPath(): """ _______________________________________________ lldb-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/lldb-commits
