urandom.c: added a FIXME so that it is not forgotten.

git-svn-id: svn://scm.gforge.inria.fr/svn/mpfr/trunk@6662 280ebfd0-de03-0410-8827-d642c229c3f4

1 files changed, 8 insertions, 0 deletions

diff --git a/urandom.c b/urandom.c
index e595257e5..7e0ef7936 100644
--- a/urandom.c
+++ b/urandom.c
@@ -26,6 +26,14 @@ http://www.gnu.org/licenses/ or write to the Free Software Foundation, Inc.,
 #define MPFR_NEED_LONGLONG_H
 #include "mpfr-impl.h"
 
+/* FIXME.
+ * - mpfr_nextabove leads to an assertion failure in reduced exponent range:
+ *   next.c:90: MPFR assertion failed: !mpfr_set_exp ((x), (exp + 1))
+ * - The algorithm itself looks wrong (the bits should be determined MSB
+ *   first in fixed point, so that there's no reason to determine the
+ *   rounding bit first). Please include a proof.
+ */
+
 int
 mpfr_urandom (mpfr_ptr rop, gmp_randstate_t rstate, mpfr_rnd_t rnd_mode)
 {