You should remove the error logic compile.c for "return" and "yield" in
function calls.

The problem with this approach is that every SyntaxError generated
during bytecode compilation must be moved to earlier. For example, I can
still use "break" and "continue" outside loops with your patch. The only
way I can think of around this is to compile the block anyway and remove
the extra code later. Maybe this optimization could be moved to the peep
holer?