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Re: Stack allocation on amd64

On 09/03/2018 12:39, Florian Weimer wrote:

> On 03/09/2018 11:28 AM, Mason wrote:
> 
>> IIUC, it's the callee's responsibility to align the stack.
> 
> On GNU, the caller has to provide 16-byte alignment.  Beyond that, the 
> callee has to do its own thing, but it can (and will) assume 16 byte 
> alignment (i.e., %rsp + 8 is a multiple of 16).

Thanks for clearing that up.

The main question remains: why is gcc allocating e.g. 24 bytes
for an 8-byte array? (N=2) 8 bytes are enough AFAICT.

Regards.
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