[MPlayer-dev-eng] [PATCH] fixes for gcc4

[Michael Niedermayer]

Hi

On Monday 28 February 2005 04:10, Gianluigi Tiesi wrote:
> On Sun, Feb 27, 2005 at 12:58:10PM +0100, Michael Niedermayer wrote:
> > Hi
> >
> > On Sunday 27 February 2005 11:00, Gianluigi Tiesi wrote:
> > > On Sat, Feb 26, 2005 at 10:56:50PM +0100, Michael Niedermayer wrote:
> >
> > [...]
> >
> > > > furthermore theres the fundamental question why exactly every project
> > > > which uses asm should rewrite their code for gcc 4, this is not about
> > > > correct or incorrect code, its practically just a syntax change
> > > > the changes gcc 4 needs makes the code much harder to read, harder to
> > > > optimize for the compiler and much longer
> > > >
> > > > is there some bugreport on gccs bugtracker about this? its breaking
> > > > code which was valid in the past
> > >
> > > There is no sense at all to assign a memory operand to a bit & binary
> > > operation,
> >
> > diagree
> >
> > > since there is no memory for this value unless you don't use a
> > > variable,
> >
> > yes, but neither is there a register to such a operation, the compiler
> > can build the value in memory so it is never in a register, its the exact
> > same situation, the compiler must put the value in a place which matches
> > the constraint, not the user, later just cant, you could also consider a
> > constraint with a specific register, its the compiler which must ensure
> > that it ends in that register, the user has no control over this
> >
> >
> > [...]
> >
> > > There is no advantage to retain a broken code even if it's more
> > > readable.
> >
> > please elaborate about why it is broken in your oppinion
>
> a binary and over two vars has not a memory location then has not an
> lvalue to put in asm code, I'm not the only that says this, if you
> disagree complain to gcc developers... :)

"m" is NOT an output, its an input only constraint, "=m" would be an output, 
so IMO theres no need for it to be a lvalue

if it where "=m" then your argument is certainly true and it would have to be 
an lvalue ...

-- 
Michael

"nothing is evil in the beginning. Even Sauron was not so." -- Elrond