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Subject: Re: does it matter how I construct an aggregate struct type if its size is the same?
To: Hayden Livingston <halivingston@gmail.com>
References: <CAMxMwy+ATViiyo4Znn4-jhmoKNEDWbHUxFPOmK6sX9_Lxd_j0w@mail.gmail.com> <5673E92C.7090400@redhat.com> <CAMxMwyJq-FH9gwvtJ3-AOnHoDUfdY2Oj8E2pSeNpHj42Wdif0g@mail.gmail.com>
Cc: libffi-discuss@sourceware.org
From: Andrew Haley <aph@redhat.com>
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Date: Fri, 18 Dec 2015 20:04:00 -0000
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On 18/12/15 15:16, Hayden Livingston wrote:
> Thanks, Andrew. Where is this exception? In ABIs?
> 
> So you're suggesting I use char's to construct my ffi_types?

Well, it can be awkward.  Some targets pass the components of a
struct in registers.  But this only matters if you pass a struct
by value, which is a fairly unusual thing to do in C.  If you're
passing a struct by reference, then yes, you can just create a
char array of the right size.

Andrew.