mypyc made my code slower

[Dreamsorcerer]

Bug Report

I really wasn't expecting this result. But, after writing a simple solution to the first advent of code problem, I thought I would see what performance can be gained by compiling it with mypyc. It was about 20% slower!

> python3 -m timeit 'from test import solve1' 'solve1()'
500 loops, best of 5: 439 usec per loop
> python3 -m timeit 'from test import solve1' 'solve1()'
500 loops, best of 5: 438 usec per loop
> mypyc  --strict test.py
...
> python3 -m timeit 'from test import solve1' 'solve1()'
500 loops, best of 5: 513 usec per loop
> python3 -m timeit 'from test import solve1' 'solve1()'
500 loops, best of 5: 513 usec per loop

To Reproduce

def solve1() -> int:
    result = 0
    for l in data:
        for c in l:
            if c.isdigit():
                result += int(c) * 10
                break
        for c in reversed(l):
            if c.isdigit():
                result += int(c)
                break
    return result

Full file with input data included:
mypy-test.txt

Expected Behavior

At worst, equal performance to pure Python.

Your Environment

• Mypy version used: 1.7.1
• Mypy command-line flags: --strict
• Python version used: 3.12