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{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Crashes and errors in test_embed with PYTHONUOPS=1","articleBody":"For a detailed report see https://github.com/python/cpython/pull/110384#issuecomment-1777657115 (a comment by @brandtbucher on a merged PR by @markshannon ).\r\n\r\nI am keeping notes about what I'm learning about this (though Mark said it's his).\r\n\r\n---\r\n\r\nThe issue seems intermittent. I can repro it by running this command repeatedly on my Mac:\r\n```\r\nPYTHONUOPS=1 ./Programs/_testembed test_run_main_loop\r\n```\r\nUsually it passes (printing 5 lines of output); occasionally I get this error:\r\n```\r\nPy_RunMain(): sys.argv=['-c', 'arg2']\r\nAssertion failed: (PyUnicode_CheckExact(ep-\u003eme_key)), function unicodekeys_lookup_unicode, file dictobject.c, line 938.\r\nAbort trap: 6\r\n```\r\n\r\n---\r\n\r\n~I can only repro this with PYTHONUOPS=1, but it never prints any uops debug output. Could it be that the issue is in the code for checking the env var?~\n\n\u003c!-- gh-linked-prs --\u003e\n### Linked PRs\n* gh-111350\n* gh-111430\n\u003c!-- /gh-linked-prs --\u003e\n","author":{"url":"https://github.com/gvanrossum","@type":"Person","name":"gvanrossum"},"datePublished":"2023-10-25T21:51:18.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":13},"url":"https://github.com/111339/cpython/issues/111339"}