René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Thread sanitizer tests failing in GitHub actions","articleBody":"**EDIT**: The cause was due to a change in LLVM's Ubuntu package.\r\n\r\nI think this is due to a ~~change in GitHub actions~~, not any particular commit. Commits that previously succeeded are now failing. I cannot reproduce the issue locally.\r\n\r\nThe only difference I see is in the reported `clang` build:\r\n\r\n`CC.version: Ubuntu clang version 18.1.8 (++20240717045746+3b5b5c1ec4a3-1~exp1~20240717165903.140)` (bad)\r\n`CC.version: Ubuntu clang version 18.1.8 (++20240714071213+3b5b5c1ec4a3-1~exp1~20240714191314.138)` (good)\r\n\r\nHowever, the runner `IMAGE_VERSION` doesn't look like it's changed:\r\n\r\n`IMAGE_VERSION: 20240714.1.0`\r\n\r\nNearly every test is failing:\r\n\r\nhttps://github.com/python/cpython/actions/runs/9982293102/job/27587742397\r\n\r\n```\r\n0:00:00 load avg: 2.83 Run 22 tests in parallel using 4 worker processes\r\n0:00:01 load avg: 2.93 [ 1/22/1] test_capi.test_pyatomic worker non-zero exit code (Exit code 66)\r\n0:00:03 load avg: 2.93 [ 2/22/2] test_code worker non-zero exit code (Exit code 66)\r\n0:00:06 load avg: 3.01 [ 3/22/3] test_functools worker non-zero exit code (Exit code 66)\r\n0:00:11 load avg: 3.01 [ 4/22/4] test_capi.test_mem worker non-zero exit code (Exit code 66)\r\n0:00:12 load avg: 3.01 [ 5/22/5] test_httpservers worker non-zero exit code (Exit code 66)\r\n0:00:16 load avg: 3.01 [ 6/22/6] test_enum worker non-zero exit code (Exit code 66)\r\n0:00:21 load avg: 3.01 [ 7/22/7] test_imaplib worker non-zero exit code (Exit code 66)\r\n0:00:39 load avg: 3.83 [ 8/22/8] test_importlib worker non-zero exit code (Exit code 66)\r\n0:00:41 load avg: 4.01 [ 9/22/9] test_logging worker non-zero exit code (Exit code 66)\r\n0:01:03 load avg: 3.79 [10/22/10] test_io worker non-zero exit code (Exit code 66) -- running (1): test_queue (42.2 sec)\r\n0:01:08 load avg: 4.21 [11/22/11] test_signal worker non-zero exit code (Exit code 66) -- running (1): test_queue (47.1 sec)\r\n0:01:09 load avg: 4.21 [12/22/12] test_sqlite3 worker non-zero exit code (Exit code 66) -- running (1): test_queue (48.0 sec)\r\n0:01:11 load avg: 4.11 [13/22/13] test_syslog worker non-zero exit code (Exit code 66) -- running (2): test_queue (50.3 sec), test_socket (30.1 sec)\r\n0:01:15 load avg: 4.82 [14/22/14] test_thread worker non-zero exit code (Exit code 66) -- running (2): test_queue (54.4 sec), test_socket (34.3 sec)\r\n0:01:17 load avg: 4.82 [15/22/15] test_threadedtempfile worker non-zero exit code (Exit code 66) -- running (2): test_queue (56.2 sec), test_socket (36.1 sec)\r\n0:01:20 load avg: 4.82 [16/22/16] test_queue worker non-zero exit code (Exit code 66) -- running (1): test_socket (39.0 sec)\r\n0:01:23 load avg: 4.68 [17/22/17] test_threading_local worker non-zero exit code (Exit code 66) -- running (1): test_socket (41.8 sec)\r\n0:01:24 load avg: 4.68 [18/22/18] test_ssl worker non-zero exit code (Exit code 66) -- running (1): test_socket (43.3 sec)\r\n0:01:29 load avg: 4.54 [19/22/19] test_threadsignals worker non-zero exit code (Exit code 66) -- running (1): test_socket (48.1 sec)\r\n0:01:50 load avg: 3.91 [20/22/20] test_weakref worker non-zero exit code (Exit code 66) -- running (2): test_threading (32.6 sec), test_socket (1 min 8 sec)\r\n0:01:53 load avg: 3.68 [21/22/21] test_socket worker non-zero exit code (Exit code 66) -- running (1): test_threading (35.4 sec)\r\n0:01:56 load avg: 3.46 [22/22/22] test_threading worker non-zero exit code (Exit code 66)\r\n\r\n```\r\n\r\nTSan logs are useless:\r\n\r\n```\r\nWARNING: ThreadSanitizer: data race (pid=8535)\r\n  Write of size 8 at 0x56136380acd0 by main thread:\r\n    #0 \u003cnull\u003e \u003cnull\u003e (python+0x31a5ee) (BuildId: 243a59[16](https://github.com/python/cpython/actions/runs/9982293102/job/27587742397#step:13:17)b2751fda530fabbdb48342727b53c0b8)\r\n    #1 \u003cnull\u003e \u003cnull\u003e (python+0x31a4a6) (BuildId: 243a5916b2751fda530fabbdb48342727b53c0b8)\r\n    #2 \u003cnull\u003e \u003cnull\u003e (python+0x4f1242) (BuildId: 243a5916b2751fda530fabbdb48342727b53c0b8)\r\n    #3 \u003cnull\u003e \u003cnull\u003e (python+0x522ef7) (BuildId: 243a5916b2751fda530fabbdb48342727b53c0b8)\r\n...\r\n```\r\n\r\n\u003c!-- gh-linked-prs --\u003e\r\n### Linked PRs\r\n* gh-121975\r\n* gh-121981\n* gh-122032\n* gh-122131\n* gh-122466\n* gh-122467\n\u003c!-- /gh-linked-prs --\u003e\r\n","author":{"url":"https://github.com/colesbury","@type":"Person","name":"colesbury"},"datePublished":"2024-07-18T03:55:23.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":9},"url":"https://github.com/121946/cpython/issues/121946"}