# Adding C API for use in tp\_traverse

**URL:** <https://discuss.python.org/t/adding-c-api-for-use-in-tp-traverse/105331>\
**Category:** C API\
**Created:** [December 17, 2025, 1:48pm UTC](https://discuss.python.org/t/adding-c-api-for-use-in-tp-traverse/105331 "2025-12-17T13:48:16Z")\
**Posts on this page:** 1\
**Showing post:** 6

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**Author:** ![emmatyping](https://sea2.discourse-cdn.com/flex002/user_avatar/discuss.python.org/emmatyping/32/36516_2.png) [@emmatyping](https://discuss.python.org/u/emmatyping)\
**Post date:** [December 19, 2025, 9:01pm UTC](https://discuss.python.org/t/adding-c-api-for-use-in-tp-traverse/105331/6 "2025-12-19T21:01:50Z")

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> [@ngoldbaum](#):
>
> > [@encukou](#):
> >
> > This currently can’t happen: both GC and MRO changes are stop-the-world operations. But that doesn’t seem like something we want to guarantee in the long term.
> 
> Maybe the stop-the-world part is the key aspect and the part that should be highlighted in the name?

As @encukou says at the end there, we probably don’t want to guarantee stop-the-world in the long-term as it’s really an implementation detail that could change. I’d like to keep the door open for a different design for the GC that may not be stop-the-world.

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