Labels don't seem to be handled correctly with Python<3.9 about bytecode HOT 5 CLOSED

Always happy to help !

from bytecode.

Just to help me follow could you post some equivalent code/pseudo-code ?

from bytecode.

This is an async_generator wrapper. This should be close to the following Python code

async def w(g):
    c = g.__anext__
    while True:
        _ = c()
        try:
            _ = await _
        except StopAsyncIteration:
            return
        try:
            s = yield _
        except GeneratorExit:
            await g.aclose()
        except:
            await g.athrow(*sys.exc_info())
        c = lambda: g.asend(s)

from bytecode.

Can you also explicit your two functions compare_exc and pop_jump_if_false, so that I know what the bytecode looks for both versions ?

from bytecode.

Big facepalm moment! Your last question helped me find the actual issue, which was due to copy-pasta in my code! 😢 These are the functions

    def compare_exc(label, lineno):
        return (
            Instr("COMPARE_OP", Compare.EXC_MATCH, lineno=lineno)
            if PY < (3, 9)
            else Instr("JUMP_IF_NOT_EXC_MATCH", label, lineno=lineno)
        )

    def jump_if_false(label, lineno):
        return Instr("POP_JUMP_IF_FALSE", label, lineno=lineno) if PY < (3, 9) else Instr("NOP", lineno=lineno)

which are defined locally inside another function. I had exc in place of label in jump_if_false. So indeed the generated bytecode was correct as it was getting exc from the outer scope! 😭 . Now that gives me RuntimeError: Failed to compute stacksize, got negative size but I should be able to fix this.

Apologies for this non-issue!

from bytecode.