Python/flowgraph.c:528: all_exits_have_lineno: Assertion `0' failed

[15r10nk]

Bug report

Bug description:

The following code causes an assertion in a debug build:

def name_4():
    try:
        pass
    except* name_3:
        pass
    else:
        return {}
    finally:
        try:
            pass
        except* name_1:
            pass

output (Python 3.13.0rc2+):

python3: Python/flowgraph.c:528: all_exits_have_lineno: Assertion `0' failed.

This bug can be reproduced with the current 3.13 branch (80de976).
I bisected the issue down to 7e49f27.
@iritkatriel I think this is one for you again.

CPython versions tested on:

3.13

Operating systems tested on:

No response

Linked PRs

• [3.13] gh-124746: remove assertion on exits having line numbers #124762

[iritkatriel]

Thanks. This commit is the one that introduced this assertion. I will remove it from 3.13 so it doesn't block releases, but will leave it in 3.14 so we can keep finding these edge cases.

[iritkatriel]

This version also crashes (return in try instead of else):

def name_4():
    try:
        return {}
    except* name_3:
        pass
    finally:
        try:
            pass
        except* name_1:
            pass

Also this one (first except* removed):

def name_4():
    try:
        return {}
    finally:
        try:
            pass
        except* name_1:
            pass

[picnixz]

@iritkatriel anything else to do here?

[iritkatriel]

These examples don't fail on 3.14 (where the assertion exists) so I guess we fixed it.