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From: Anthony Green <green@moxielogic.com>
To: Andrew Haley <aph@redhat.com>
Cc: libffi-discuss <libffi-discuss@sourceware.org>
Subject: Re: How to call 'printf' using libffi?
Date: Fri, 19 Mar 2021 07:01:35 -0400	[thread overview]
Message-ID: <CACxje589M=irBhUGC+LLdVCF5fUFdkY6pHwo6CQgw3=bEWzVzg@mail.gmail.com> (raw)
In-Reply-To: <7c8729d8-d10e-cdb8-5518-e2f82ccbe141@redhat.com>

On Fri, Mar 19, 2021 at 6:13 AM Andrew Haley via Libffi-discuss <
libffi-discuss@sourceware.org> wrote:

> On 3/18/21 3:25 PM, Anthony Green wrote:
> >   arg_types[0] = &ffi_type_pointer;
> >   arg_types[1] = &ffi_type_double;
> >   arg_types[2] = &ffi_type_sint;
> >   arg_types[3] = NULL;
> >
> >   /* This printf call is variadic */
> >   ffi_prep_cif_var(&cif, FFI_DEFAULT_ABI, 1, 3, &ffi_type_sint,
> arg_types);
>
> Surely that only works if a varargs call uses the same ABI as a normal
> call. They don't always,
>

I'm using the '_var' variant of ffi_prep_cif that takes this into account.

AG

  reply	other threads:[~2021-03-19 11:01 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-03-18 14:04 ShaJunxing
2021-03-18 15:25 ` Anthony Green
2021-03-19  2:08   ` ShaJunxing
2021-03-19  2:36     ` Kaz Kylheku (libffi)
2021-03-19  3:09       ` ShaJunxing
2021-03-19 10:13   ` Andrew Haley
2021-03-19 11:01     ` Anthony Green [this message]
2021-03-19 11:43       ` Andrew Haley
2021-03-20 22:40         ` Anthony Green
2021-03-20 23:56           ` Anthony Green
2021-03-22 10:36             ` Andrew Haley
2021-03-19 11:26     ` Jarkko Hietaniemi
2021-03-19 11:33       ` Anthony Green

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