[Ffmpeg-devel] [PATCH] '/nop' illegal for old versions of GAS

[Ivan Kalvachev]

2006/7/27, Rich Felker <dalias at aerifal.cx>:
> On Wed, Jul 26, 2006 at 11:20:56AM +0200, Michael Niedermayer wrote:
> > Hi
> >
> > On Wed, Jul 26, 2006 at 01:10:31PM +1000, Nigel Pearson wrote:
> > [...]
> > > >heres what the gas manual says about lines starting with #
> > > >---
> > > >To be compatible with past assemblers, lines that begin with `#'
> > > >have a special interpretation.  Following the `#' should be an absolute
> > > >expression (*note Expressions::): the logical line number of the _next_
> > > >line.  Then a string (*note Strings: Strings.) is allowed: if present
> > > >it is a new logical file name.  The rest of the line, if any, should be
> > > >whitespace.
> > >
> > >     Yes, but it goes on...
> > >
> > > If the first non-whitespace characters on the line are not numeric, the
> > > line is ignored. (Just like a comment.)
> > >
> > >
> > >     nop is is not a numeric expression, but to be
> > > perfect, the line should be something like " # nop"?
> > > Sadly, that requires re-writing of the macros.
> >
> > if you do that, use #define NOP " # nop" and then use NOP
>
> I hope this change or something similar is acceptable to you, since
> I'll be using the same assembler code (based on gas 1.38) on my
> i386-linux. :) Apple was actually rather smart in choosing something
> gas-1.38-based since all the newer versions use libbfd.

If I remember right 'nop' is actually 'mov eax,eax'. Would the
assembler accept that form?