Skip to content

GH-118074: Executors in the COLD_EXITS array are not GC'able #118117

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 4 commits into from
Apr 22, 2024
Merged

GH-118074: Executors in the COLD_EXITS array are not GC'able #118117

Changes from 2 commits
Commits
Show all changes
4 commits
Select commit Hold shift + click to select a range
f2e10eb
Executors in the COLD_EXITS array are not GC'able
gvanrossum Apr 20, 2024
e748e8a
Fix address arithmetic bug
gvanrossum Apr 20, 2024
bb71ae9
Use correct COLD_EXITS upper bound
gvanrossum Apr 22, 2024
1653fe5
Add blurb
gvanrossum Apr 22, 2024
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
10 changes: 10 additions & 0 deletions Python/optimizer.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -394,6 +394,15 @@ executor_traverse(PyObject *o, visitproc visit, void *arg)
return 0;
}

static int
executor_is_gc(PyObject *o)
{
if ((PyObject *)&COLD_EXITS[0] <= o && o < (PyObject *)&COLD_EXITS[UOP_MAX_TRACE_LENGTH]) {
Copy link
Contributor

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

The address sanitizer warning here seems plausibly correct:

array subscript 800 is above array bounds of ‘_PyExecutorObject[200]’ [-Warray-bounds]

COLD_EXITS has a length of UOP_MAX_TRACE_LENGTH/4. If there's some other reason this is correct, maybe add a comment / a way to suppress the warning?

Copy link
Member Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Oh, you're right. That line was written by Copilot and it looked so plausible but was so wrong. :-(

return 0;
}
return 1;
}

PyTypeObject _PyUOpExecutor_Type = {
PyVarObject_HEAD_INIT(&PyType_Type, 0)
.tp_name = "uop_executor",
Expand All @@ -405,6 +414,7 @@ PyTypeObject _PyUOpExecutor_Type = {
.tp_methods = executor_methods,
.tp_traverse = executor_traverse,
.tp_clear = executor_clear,
.tp_is_gc = executor_is_gc,
};

/* TO DO -- Generate these tables */
Expand Down