Re: (elisp)Numbers

["Eli Zaretskii" <eliz@elta.co.il>]

> Date: Fri, 24 Oct 2003 15:50:41 +0200
> From: "Eli Zaretskii" <eliz@elta.co.il>
> 
> > From: Andreas Schwab <schwab@suse.de>
> > Date: Fri, 24 Oct 2003 10:43:06 +0200
> > >
> > > also, i compile with -O0.  should that really open-code sqrt?
> > 
> > Please check that sqrt is not a macro.
> 
> Yes, it seems that sqrt is expanded into inline code that always
> issues the FSQRT instruction, and doesn't set errno.

Here's the code I see with "gcc -E -O2" on fencepost (I reformatted it
for better readability):

    extern __inline double sqrt ( double __x) 
    { 
      register double __result;
      __asm __volatile__ ( "fsqrt" : "=t" (__result) : "0" (__x) );
       return __result; 
    }

As you see, it never sets errno.