Thanks for replying; you brought my attention back to this problem, which caused me to think more about it. Turns out, there is a shorter solution. It uses an entirely different idea. Here it is:

int
exit();
main()
{}

This compiles with g++ and runs with Python 3.11 (probably works with 3.12 too). It is 1 byte shorter than my previous solution.

An even shorter solution can be compiled with gcc as C source code, but doesn't compile with g++ as C++ source code:

exit();
main()
{}