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From: Hayden Livingston <halivingston@gmail.com>
To: libffi-discuss@sourceware.org
Subject: does it matter how I construct an aggregate struct type if its size is the same?
Date: Fri, 18 Dec 2015 06:47:00 -0000	[thread overview]
Message-ID: <CAMxMwy+ATViiyo4Znn4-jhmoKNEDWbHUxFPOmK6sX9_Lxd_j0w@mail.gmail.com> (raw)

This may be a fundamental question, but does it matter how a struct is
constructed if its size is accurate to the receiving function? That is
if it was made up of all int8s vs. a combination of other types?

My scenario is that I have a receiving function whose actual struct
type information I do not know, but I know its size, so I was thinking
I could just build it up using int8 ffi_type and hope for the best.

Is this correct in the most popular ABIs (x86, x64, arm -
windows/Linux/macosx) that all the ABI and compilers that generate
code respecting those ABI care only about size and alignment?

I suspect so, but I'm not sure if there are quirks? Maybe on Windows?

Thanks!

             reply	other threads:[~2015-12-18  6:47 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-12-18  6:47 Hayden Livingston [this message]
2015-12-18  6:50 ` Hayden Livingston
2015-12-18 11:08 ` Andrew Haley
2015-12-18 15:16   ` Hayden Livingston
2015-12-18 20:04     ` Andrew Haley
2015-12-18 21:42       ` Jay
2015-12-18 22:16         ` Hayden Livingston
2015-12-18 22:24           ` Andrew Haley
2015-12-18 23:10             ` Hayden Livingston

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