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Re: [patch libffi]: Add thiscall-closure support for fixing regression PR/51500
2012/1/31 Uros Bizjak <ubizjak@gmail.com>:
> On Tue, Jan 31, 2012 at 10:51 AM, Kai Tietz <ktietz70@googlemail.com> wrote:
>> Ok, this variant keeps 16-byte alignment for thiscall-closure.
>
> It doesn't. You have to account for the fact that caller pushed return
> address to the stack, so %esp was already decreased by 4 behind your
> back. To maintain alignment, you have to decrease %esp by $12, not by
> $16.
>
> Uros.
Ah, I got you. Right before call stack is aligned, in call we have
unaligned return-address already on stack. I fix that
Kai