Description

dimpolo

opened on Mar 11, 2022

Issue body actions

n = 0

class Test:
    def __bool__(self):
        global n
        n += 1
        return False

Test() and False or False
assert n == 1

CPython optimizes this check in:
https://github.com/python/cpython/blob/54ab9ad312ea53db40e31712454272e1d4c0315f/Python/compile.c#L8708-L8721

Reacted by Jeong, YunWon and Snowapril

Activity

1. crazymerlyn commented on Sep 7, 2024

   

   crazymerlyn

   on Sep 7, 2024

   Contributor

   More actions

   Looks like the assertion fails again since python 3.12: https://godbolt.org/z/qoKcdvz4T
2. moreal commented on Feb 14, 2026

   

   moreal

   on Feb 14, 2026

   Contributor

   More actions

   In CPython 3.14, the assertion has started to pass again.

   https://godbolt.org/z/1Genzf9sE

   
3. moreal

   added 2 commits that reference this issue on Feb 15, 2026

   Add runtime test for redundant __bool__ check (issue RustPython#3567)

   42e08bd

   Add runtime test for redundant __bool__ check (issue RustPython#3567)

   d8ccc98
4. youknowone

   closed this as completedin #7176on Feb 17, 2026
5. youknowone

   added a commit that references this issue on Feb 17, 2026

   Optimize redundant bool check (#7176)

   d07d522
6. youknowone

   added a commit that references this issue on Mar 22, 2026

   Optimize redundant bool check (RustPython#7176)

   18f5812
7. youknowone

   added a commit that references this issue on Sep 16, 2026

   Optimize redundant bool check (#7176)

   4b292f4

Issue actions