log.dat: add example with intermediate underflow

log.c: handle intermediate underflow


git-svn-id: svn://scm.gforge.inria.fr/svn/mpc/trunk@1209 211d60ee-9f03-0410-a15a-8952a2c7a4e4

1 files changed, 2 insertions, 2 deletions

diff --git a/src/log.c b/src/log.c
index 5358ee6..d9f19fd 100644
--- a/src/log.c
+++ b/src/log.c
@@ -144,8 +144,8 @@ do {                                                            \
       /* w is rounded down */
       inex = mpc_norm (w, op, GMP_RNDN);
          /* error 0.5 ulp */
-      if (mpfr_inf_p (w))
-         /* intermediate overflow; the logarithm may be representable */
+      if (mpfr_inf_p (w) || mpfr_zero_p (w))
+         /* intermediate over- or underflow; the logarithm may be representable */
          break;
       if (inex && mpfr_cmp_ui (w, 1) == 0)
          /* this is like an underflow; the following call to log will