[ruby-core:30937] Re: [Bug #3487] fiddle pushes arguments in a wrong format

On Sun, Jun 27, 2010 at 08:36:45PM +0900, Yuki Sonoda wrote:
> Bug #3487: fiddle pushes arguments in a wrong format
> http://redmine.ruby-lang.org/issues/show/3487
> 
> Author: Yuki Sonoda
> Status: Assigned, Priority: Normal
> Assigned to: Aaron Patterson, Target version: 1.9.2
> ruby -v: ruby 1.9.2dev (2010-06-25 revision 28427) [i386-darwin9.8.0]
> 
> DL::TestImport#test_qsort fails on Mac OS X 10.5 when
> * Ruby is compiled with the universal binary version of libffi.
>   * It does not reproduce even when Ruby is dynamically linked with the libffi, if Ruby is compiled with a libffi which is not universal binary.
> * And ruby is compiled for i386.
> 
> and here is a copy of the mail I sent to report the problem to tenderlove:
> ---
> Hi,
> 
> Here's a log:
>  1) Failure:
> test_qsort(DL::TestImport)
> [/Users/yugui/dev/ruby/mri/1.9.2/test/dl/test_import.rb:148]:
> <"1349"> expected but was
> <"9341">.
> 
> == Problem
> The problem is fiddle regards rb_ffi_type_of(long) as ffi_type_sint64
> even if complied for i386 but not for x86_64.
> So libffi set up a wrong stack for qsort.
> 
> There are two reasons. The first reason is a problem of macports:
> * https://trac.macports.org/ticket/25439
> MacPorts installs a invalid header ffitarget.h, so
> ext/fiddle/extconf.rb fails to detect libffi installed by MacPorts.
> This happens when
> * MacPorts uses +universal variant for libffi
> * fiddle is compiled with the universal libffi
> * universal_archs option for MacPorts includes both ppc and i386
> 
> The other reason is /usr/include/ffi/ffitarget.h on OSX Leopard.
> OSX Leopard uses i386 arch by default, however, the ffitarget.h is
> configured as sizeof(long)==8.
> 
> fiddle uses /usr/include/ffi/ffi.h instiead of
> /opt/local/lib/libffi-3.0.9/include/ffi.h and it uses
> # define ffi_type_slong ffi_type_sint64.
> 
> == Reproduction
> In http://twitter.com/tenderlove/status/17103559909:
> > I can't seem to reproduce.
> 
> I think you uses OSX Snow Leopard, so gcc compiles ruby for x86_64 by
> default. sizeof(long) == 8 is correct in this case.
> Could you try ./configure --with=arch=i386 for Ruby's configuration?
> 
> == Solution
> I succeeded to avoid this problem by overwriting the aliases based on
> Ruby's configuration as the following patch:
> * http://gist.github.com/454779
> 
> I think it is enough because libffi seems to assume CHAR_BIT == 8.
> What do you think?

This patch fixed the tests when running arch i386 for me, but broke the
tests when using 64 bit (no parameters to configure).

Can you try out this patch?  It worked for me with i386 and x86 64.

  http://gist.github.com/455472

Thanks!

-- 
Aaron Patterson
http://tenderlovemaking.com/