[FFmpeg-devel] [Ffmpeg-devel] [PATCH] detect support for 10 operands in configure

[Måns Rullgård]

Loren Merritt <lorenm at u.washington.edu> writes:

> On Mon, 9 Feb 2009, Diego Biurrun wrote:
>
>> I think this is the proper solution for the gcc 2.95 breakage that just
>> occurred.  Probably there is a better way to write the check, but it
>> seems to work and I know no Assembler.
>
> Your patch implicitly checks have_7regs too.
>
> --Loren Merritt
>
> Index: configure
> ===================================================================
> --- configure	(revision 17097)
> +++ configure	(working copy)
> @@ -898,6 +900,7 @@
>      sys_select_h
>      sys_soundcard_h
>      sys_videoio_h
> +    ten_operands
>      termios_h
>      threads
>      truncf
> @@ -1778,6 +1782,19 @@
>      # check wether EBX is available on x86
>      check_asm ebx_available '"":::"%ebx"'
>
> +    # check whether more than 10 operands are supported
> +    check_cc -O1 <<EOF && enable ten_operands
> +int main(void)
> +{
> +    int x=0;
> +    __asm__ volatile(
> +        "nop\n"

You could even make that an empty string.  GCC doesn't care.

> +        :"+&rm"(x), "+&rm"(x), "+&rm"(x), "+&rm"(x), "+&rm"(x), "+&rm"(x)

Does & make a difference with +?

-- 
M?ns Rullg?rd
mans at mansr.com