[Ffmpeg-devel] Mac OS X Intel last part: balign directives

Rich Felker dalias
Fri Aug 18 19:10:25 CEST 2006

On Sat, Aug 12, 2006 at 10:59:14AM +1000, John Dalgliesh wrote:
> >but i have the feeling that the configure part will
> >need amendment as old gas had the habit of assembling anything no matter
> >if the instructions existed or not, so i wouldnt be surprised if some gas
> >versions would accept .align 3 even though they arent using 3 as exponent
> Possibly. The oldest (mainline) gas I can easily find is from 1996, and it 
> does check that the arg is a power of two. I doubt we will find another 
> little gem like Apple's that can 1) assemble code where alignment provides 
> some benefit* (so uses ASMASLIGN) and 2) doesn't check arg is POT if 
> provided as NPOT.

I have and use gas 1.38 from 1990 and it contains (in read.c):

    if (temp != 1)
        as_bad("Alignment not a power of 2");

therefore I think it's safe. :)


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