[Bug middle-end/21718] real.c rounding not perfect

["exploringbinary at gmail dot com" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21718

--- Comment #26 from Rick Regan <exploringbinary at gmail dot com> ---
So the problem was never lack of precision -- just lack of stickiness. We were
seeing higher precision making more conversions work (e.g., more worked with
192 bits than 160), but ultimately, stickiness was required to augment the
limited precision. This will fix the architecture-dependent aspect of the bug
as well.

I suppose you could have fixed the existing algorithm, although admittedly
using MPFR is a simple and elegant solution. BTW, why was this fixed now, and
not when an MPFR based solution was discussed four/five/six years ago? You
certainly could have done it a few weeks ago, before I wrote all those articles
:).