[PATCH] math: add LDBL_CLASSIFY_COMPAT support

[Joseph Myers]

On Thu, 3 Dec 2015, Chris Metcalf wrote:

> Joseph, is that what you had in mind?  Passes tests on tilegx, and
> I confirmed that enabling LDBL_CLASSIFY_COMPAT for tilegx generated
> plausible compat symbols.

Yes, this is what I had in mind.  OK with changes as noted.  This should 
also allow the hppa patch 
<https://sourceware.org/ml/libc-alpha/2015-11/msg00520.html> to work 
without introducing bogus exports, though that patch needs review by an 
hppa person.

>  sysdeps/ieee754/dbl-64/wordsize-64/s_finite.c      |  6 +++++-
>  sysdeps/ieee754/dbl-64/wordsize-64/s_isinf.c       |  5 ++++-
>  sysdeps/ieee754/dbl-64/wordsize-64/s_isnan.c       |  5 ++++-

You need to change both the wordsize-64 and non-wordsize-64 files.

>  #ifdef NO_LONG_DOUBLE
> -strong_alias (__finite, __finitel)
> +# if defined LDBL_CLASSIFY_COMPAT && SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_23)
> +compat_symbol (libc, __finite, __finitel, GLIBC_2_0);
> +compat_symbol (libm, __finite, __finitel, GLIBC_2_0);
> +# endif

Here and in the other s_finite.c, you should have separate SHLIB_COMPAT 
conditionals around the libc and libm compat_symbol calls (each one having 
a SHLIB_COMPAT conditional for the right library).

> diff --git a/sysdeps/m68k/coldfire/fpu/math_private.h b/sysdeps/m68k/coldfire/fpu/math_private.h
> new file mode 100644
> index 000000000000..d13f2d49d3ee
> --- /dev/null
> +++ b/sysdeps/m68k/coldfire/fpu/math_private.h
> @@ -0,0 +1,10 @@
> +#ifndef SH_MATH_PRIVATE_H
> +#define SH_MATH_PRIVATE_H 1

This of course should be COLDFIRE_MATH_PRIVATE_H.

-- 
Joseph S. Myers
joseph@codesourcery.com