Always duplicate the method name in zend_get_call_trampoline_func().

[LawnGnome]

This fixes bug #71778 (which has more detail), and ensures that there isn't inconsistent behaviour in zend_get_call_trampoline_func() (and, probably more importantly from an actual use perspective, zend_std_get_method() by extension).

This doesn't apply to 5.x, so the PR is against 7.0 for easy merging up to master.

[nikic]

I don't understand what you are trying to fix here (having read the bug report). Your code snippet in the bug report will not free method_name, yes, but only because it is still used elsewhere.

[LawnGnome]

@nikic How is func->function_name freed in the general case? We're seeing a leak as a result of this: is that because there's an underlying assumption that the zend_function * returned from zend_std_get_method() will then be invoked?

[nikic]

If you get a CALL_VIA_TRAMPOLINE function and you don't call it, you are responsible for freeing the function name and calling zend_free_trampoline.

[LawnGnome]

@nikic Cheers; that would explain that, then. Is that just true of zend_std_get_method()? (I'll update the Wiki to document that, since I don't think it's written down anywhere — at least that I've found, anyway.)