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Re: Gcc builtin functions used by glibc not available on mips

"H . J . Lu" <> writes:
> > In glibc, there are codes
> > 
> >   /* Partly clean the `bootstrap_map' structure up.  Don't use
> >      `memset' since it might not be built in or inlined and we cannot
> >      make function calls at this point.  Use '__builtin_memset' if we
> >      know it is available.  */
> > #if __GNUC_PREREQ (2, 96) 
> >   __builtin_memset (bootstrap_map.l_info, '\0', sizeof (bootstrap_map.l_info));
> > #else
> >   for (cnt = 0;
> >        cnt < sizeof (bootstrap_map.l_info) / sizeof (bootstrap_map.l_info[0]);
> >        ++cnt)
> >     bootstrap_map.l_info[cnt] = 0;
> > #endif

Geoffry Keating writes:
> GCC does not promise that __builtin_memset will be inlined.  Whether
> it calls memset() can depend on details such as which CPU was selected
> to tune for (eg. Pentium III vs. Pentium 4).

Is builtin_memset really enough of a win over the for loop in this context
that it's even worth messing with this stuff?

Why not just get rid of the ifdef and use the else part always?

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