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Re: __attribute__ ((packed))

> Philippe De Muyter wrote:
> > 
> > The test below is not strong enough to decide __attribute__ ((packed)) is
> > supported.  Perhaps the best way, if `packed' is really needed, would be
> > to do an autoconf test.
> > 
> > Thu May  6 12:32:55 1999  Philippe De Muyter  <phdm@macqel.be>
> > 
> >         * include/elf/external.h (Elf_External_Versym) : __attribute__ ((
> >         packed)) turned off.
> > 
> > --- ./include/elf/external.h    Thu May  6 12:34:15 1999
> > +++ ./include/elf/external.h    Wed Apr 28 13:37:55 1999
> > @@ -241,8 +241,10 @@
> >  typedef struct {
> >    unsigned char                vs_vers[2];
> >  }
> > +#if 0
> >  #ifdef __GNUC__
> >    __attribute__ ((packed))
> > +#endif
> >  #endif
> >    Elf_External_Versym;
> > 
> 
> This change will break some of the ELF code on the ARM.  There are places in the
> code where sizeof(Elf_External_Versym) is used, and is expected to be 2.  On the
> ARM without the packed attribute this struct will be 4 bytes in length.
> 
> Scott
> 
Then, I think that this should written to not depend of the compiler used
to compile this code.

Philippe