René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Segfault from running `os.pathconf(-1, 1)`","articleBody":"# Crash report\n\n### What happened?\n\nThe following code will segfault on Python 3.13, 3.14 and main (3.15).\n\n```python\nimport os\nos.pathconf(-1, 1)\n```\n\n\u003cdetails\u003e\u003csummary\u003eBacktrace\u003c/summary\u003e\n\u003cp\u003e\n\n\n```\nProgram received signal SIGSEGV, Segmentation fault.\n\n#0  __pathconf (file=0x0, name=name@entry=1) at ../sysdeps/unix/sysv/linux/pathconf.c:58\n#1  0x00005555561fd98d in os_pathconf_impl (module=0x7ccff6fecd20, path=0x7bfff5d00040, name=1) at ./Modules/posixmodule.c:14335\n#2  os_pathconf (module=\u003coptimized out\u003e, args=0x7bfff5dfff28, nargs=\u003coptimized out\u003e, kwnames=\u003coptimized out\u003e) at ./Modules/clinic/posixmodule.c.h:10539\n#3  0x0000555555bfa45c in cfunction_vectorcall_FASTCALL_KEYWORDS (func=func@entry=0x7c7ff7065bc0, args=args@entry=0x7bfff5dfff28, nargsf=nargsf@entry=9223372036854775810,\n    kwnames=kwnames@entry=0x0) at Objects/methodobject.c:465\n#4  0x0000555555ad5f80 in _PyObject_VectorcallTstate (tstate=0x555556a159c8 \u003c_PyRuntime+360584\u003e, callable=0x7c7ff7065bc0, args=0x7bfff5dfff28, nargsf=9223372036854775810, kwnames=0x0)\n    at ./Include/internal/pycore_call.h:136\n#5  0x0000555555e7399d in _Py_VectorCallInstrumentation_StackRefSteal (callable=..., arguments=\u003coptimized out\u003e, total_args=2, kwnames=..., call_instrumentation=\u003coptimized out\u003e,\n    frame=\u003coptimized out\u003e, this_instr=\u003coptimized out\u003e, tstate=\u003coptimized out\u003e) at Python/ceval.c:769\n#6  0x0000555555eaf560 in _PyEval_EvalFrameDefault (tstate=\u003coptimized out\u003e, frame=\u003coptimized out\u003e, throwflag=\u003coptimized out\u003e) at Python/generated_cases.c.h:1817\n#7  0x0000555555e72838 in _PyEval_EvalFrame (tstate=0x555556a159c8 \u003c_PyRuntime+360584\u003e, frame=0x7e8ff6fe5220, throwflag=0) at ./Include/internal/pycore_ceval.h:118\n#8  _PyEval_Vector (tstate=\u003coptimized out\u003e, func=\u003coptimized out\u003e, locals=\u003coptimized out\u003e, args=\u003coptimized out\u003e, argcount=\u003coptimized out\u003e, kwnames=0x0) at Python/ceval.c:2132\n#9  0x0000555555e72255 in PyEval_EvalCode (co=\u003coptimized out\u003e, globals=\u003coptimized out\u003e, locals=0x7c7ff70893c0) at Python/ceval.c:680\n#10 0x000055555613d66f in run_eval_code_obj (tstate=tstate@entry=0x555556a159c8 \u003c_PyRuntime+360584\u003e, co=co@entry=0x7d1ff7019650, globals=globals@entry=0x7c7ff70893c0,\n    locals=locals@entry=0x7c7ff70893c0) at Python/pythonrun.c:1366\n#11 0x000055555613c83c in run_mod (mod=\u003coptimized out\u003e, filename=\u003coptimized out\u003e, globals=\u003coptimized out\u003e, locals=\u003coptimized out\u003e, flags=\u003coptimized out\u003e, arena=\u003coptimized out\u003e,\n    interactive_src=\u003coptimized out\u003e, generate_new_source=\u003coptimized out\u003e) at Python/pythonrun.c:1469\n#12 0x0000555556136e3d in pyrun_file (fp=fp@entry=0x7d4ff6fef800, filename=filename@entry=0x7ccff6ffbbf0, start=start@entry=257, globals=globals@entry=0x7c7ff70893c0,\n    locals=locals@entry=0x7c7ff70893c0, closeit=closeit@entry=1, flags=0x7bfff5e1eb10) at Python/pythonrun.c:1294\n#13 0x000055555613499d in _PyRun_SimpleFileObject (fp=\u003coptimized out\u003e, filename=\u003coptimized out\u003e, closeit=\u003coptimized out\u003e, flags=\u003coptimized out\u003e) at Python/pythonrun.c:518\n#14 0x0000555556133d0e in _PyRun_AnyFileObject (fp=fp@entry=0x7d4ff6fef800, filename=filename@entry=0x7ccff6ffbbf0, closeit=closeit@entry=1, flags=flags@entry=0x7bfff5e1eb10)\n    at Python/pythonrun.c:81\n#15 0x00005555561b215b in pymain_run_file_obj (program_name=0x7caff7027bc0, filename=0x7ccff6ffbbf0, skip_source_first_line=0) at Modules/main.c:410\n#16 pymain_run_file (config=0x5555569e0a48 \u003c_PyRuntime+143624\u003e) at Modules/main.c:429\n#17 0x00005555561b0224 in pymain_run_python (exitcode=0x7bfff5e1e700) at Modules/main.c:691\n#18 Py_RunMain () at Modules/main.c:772\n#19 0x00005555561b1127 in pymain_main (args=\u003coptimized out\u003e) at Modules/main.c:802\n#20 0x00005555561b1298 in Py_BytesMain (argc=\u003coptimized out\u003e, argv=0x7fffffffdb48) at Modules/main.c:826\n#21 0x00007ffff7c2a575 in __libc_start_call_main (main=main@entry=0x55555590bc40 \u003cmain\u003e, argc=argc@entry=2, argv=argv@entry=0x7fffffffdb48) at ../sysdeps/nptl/libc_start_call_main.h:58\n#22 0x00007ffff7c2a628 in __libc_start_main_impl (main=0x55555590bc40 \u003cmain\u003e, argc=2, argv=0x7fffffffdb48, init=\u003coptimized out\u003e, fini=\u003coptimized out\u003e, rtld_fini=\u003coptimized out\u003e,\n    stack_end=0x7fffffffdb38) at ../csu/libc-start.c:360\n#23 0x00005555558224f5 in _start ()\n```\n\n\u003c/p\u003e\n\u003c/details\u003e\n\n\nFound using [fusil](https://github.com/devdanzin/fusil) by @vstinner.\n\n\n### CPython versions tested on:\n\nCPython main branch, 3.14, 3.13\n\n### Operating systems tested on:\n\nLinux\n\n### Output from running 'python -VV' on the command line:\n\nPython 3.15.0a6+ (heads/main-dirty:5e61a16c105, Feb 24 2026, 19:33:58) [Clang 21.1.2 (2ubuntu6)]\n\n\u003c!-- gh-linked-prs --\u003e\n### Linked PRs\n* gh-145341\n* gh-145390\n* gh-145432\n* gh-145433\n* gh-145439\n* gh-145528\n\u003c!-- /gh-linked-prs --\u003e\n","author":{"url":"https://github.com/devdanzin","@type":"Person","name":"devdanzin"},"datePublished":"2026-02-27T23:17:24.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":1},"url":"https://github.com/145335/cpython/issues/145335"}