re PR fortran/47642 (real(kind=16) - libquadmath - segfault on amd64 FreeBSD)

re PR fortran/47642 (real(kind=16) - libquadmath - segfault on amd64 FreeBSD)

	PR fortran/47642
	* libquadmath.texi (quadmath_snprintf): Document.
	(quadmath_flt128tostr): Remove.
	* Makefile.am (libquadmath_la_SOURCES): Add printf/*.c.
	Remove  quadmath_io.c, gdtoa/gdtoa.c, gdtoa/g__fmt.c,
	gdtoa/g_Qfmt.c, gdtoa/dmisc.c and gdtoa/ulp.c.
	* quadmath.h (quadmath_snprintf): New prototype.
	(quadmath_flt128tostr): Remove.
	* quadmath_weak.h (quadmath_snprintf): Add.
	(quadmath_flt128tostr): Remove.
	* configure.ac: New AC_CHECK_HEADERS headers: langinfo.h, wchar.h,
	wctype.h, limits.h, ctype.h, printf.h, errno.h.
	(AC_USE_SYSTEM_EXTENSIONS): Add.
	(HAVE_HIDDEN_VISIBILITY, HAVE_PRINTF_HOOKS,
	USE_LOCALE_SUPPORT, USE_I18N_NUMBER_H): New checks.
	* quadmath.map (QUADMATH_1.0): Add quadmath_snprintf.  Remove
	quadmath_flt128tostr.
	* printf/printf_fphex.c: New file.
	* printf/_itowa.h: New file.
	* printf/mul_n.c: New file.
	* printf/quadmath-printf.h: New file.
	* printf/submul_1.c: New file.
	* printf/quadmath-printf.c: New file.
	* printf/gmp-impl.h: New file.
	* printf/lshift.c: New file.
	* printf/fpioconst.h: New file.
	* printf/add_n.c: New file.
	* printf/cmp.c: New file.
	* printf/sub_n.c: New file.
	* printf/mul.c: New file.
	* printf/divrem.c: New file.
	* printf/addmul_1.c: New file.
	* printf/printf_fp.c: New file.
	* printf/_itoa.h: New file.
	* printf/fpioconst.c: New file.
	* printf/_i18n_number.h: New file.
	* printf/flt1282mpn.c: New file.
	* printf/rshift.c: New file.
	* printf/mul_1.c: New file.
	* quadmath_io.c: Removed.
	* gdtoa/gdtoa.c: Removed.
	* gdtoa/g__fmt.c: Removed.
	* gdtoa/g_Qfmt.c: Removed.
	* gdtoa/dmisc.c: Removed.
	* gdtoa/ulp.c: Removed.
	* config.h.in: Regenerated.
	* configure: Regenerated.
	* Makefile.in: Regenerated.

	* io/write_float.def (DTOAQ): Use quadmath_snprintf instead of
	quadmath_flt128tostr.
	* io/transfer128.c (tmp2): Initialize to quadmath_snprintf instead
	of quadmath_flt128tostr.

From-SVN: r170135