Eryk Sun <eryk...@gmail.com> added the comment:

It should be fine. If the docs don't require initializing cb, we can assume 
it's done for us. 

For example, msvcrt.dll calls GetStartupInfo without initializing this field:

    0:000> kc 3
    Call Site
    KERNELBASE!GetStartupInfoW
    msvcrt!ioinit
    msvcrt!__CRTDLL_INIT

In x64, the first argument (lpStartupInfo) is in rcx. We see the DWORD (dd) 
value of cb is initially 0:

    0:000> dd @rcx l1
    00000094`25ddefd0  00000000

Continue to the ret[urn] instruction via pt and check that the returned value 
of cb is sizeof(*lpStartupInfo):

    0:000> pt
    KERNELBASE!GetStartupInfoW+0xb2:
    00007fff`8ae41282 c3              ret
    0:000> dd 94`25ddefd0 l1
    00000094`25ddefd0  00000068

----------

_______________________________________
Python tracker <rep...@bugs.python.org>
<https://bugs.python.org/issue32560>
_______________________________________
_______________________________________________
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

Reply via email to