The cast to uintmax_t wasn't really useful, so I removed it.

Added a comment.


git-svn-id: svn://scm.gforge.inria.fr/svn/mpfr/trunk@3014 280ebfd0-de03-0410-8827-d642c229c3f4

1 files changed, 10 insertions, 2 deletions

diff --git a/get_sj.c b/get_sj.c
index 87269b7c0..0e06f08e3 100644
--- a/get_sj.c
+++ b/get_sj.c
@@ -94,9 +94,16 @@ mpfr_get_sj (mpfr_srcptr f, mpfr_rnd_t rnd)
           for (n = MPFR_LIMB_SIZE (x) - 1; n >= 0; n--)
             {
               sh -= BITS_PER_MP_LIMB;
+              /* Note the concerning the casts below:
+                 When sh >= 0, the cast must be performed before the shift
+                 for the case sizeof(intmax_t) > sizeof(mp_limb_t).
+                 When sh < 0, the cast must be performed after the shift
+                 for the case sizeof(intmax_t) == sizeof(mp_limb_t), as
+                 mp_limb_t is unsigned, therefore not representable as an
+                 intmax_t when the MSB is 1 (this is the case here). */
               r += (sh >= 0
                     ? (intmax_t) xp[n] << sh
-                    : (intmax_t) ((uintmax_t) xp[n] >> (-sh)));
+                    : (intmax_t) (xp[n] >> (-sh)));
             }
         }
       else
@@ -104,9 +111,10 @@ mpfr_get_sj (mpfr_srcptr f, mpfr_rnd_t rnd)
           for (n = MPFR_LIMB_SIZE (x) - 1; n >= 0; n--)
             {
               sh -= BITS_PER_MP_LIMB;
+              /* See above for the note concerning the casts. */
               r -= (sh >= 0
                     ? (intmax_t) xp[n] << sh
-                    : (intmax_t) ((uintmax_t) xp[n] >> (-sh)));
+                    : (intmax_t) (xp[n] >> (-sh)));
             }
         }
     }