added two tests for 0-c and c-0 with prec(c) > prec(a)

git-svn-id: svn://scm.gforge.inria.fr/svn/mpfr/trunk@1311 280ebfd0-de03-0410-8827-d642c229c3f4

1 files changed, 16 insertions, 0 deletions

diff --git a/tests/tsub.c b/tests/tsub.c
index 722c37f0f..7e03d3cb2 100644
--- a/tests/tsub.c
+++ b/tests/tsub.c
@@ -229,6 +229,22 @@ check_diverse ()
       exit (1);
     }
 
+  mpfr_set_prec (x, 1);
+  mpfr_set_prec (y, 10);
+  mpfr_set_prec (z, 10);
+  mpfr_set_ui (y, 0, GMP_RNDN);
+  mpfr_set_str_raw (z, "0.100000000000000000000100E15");
+  if (mpfr_sub (x, y, z, GMP_RNDN) <= 0)
+    {
+      fprintf (stderr, "Wrong inexact flag in x=mpfr_sub(0,z) for prec(z)>prec(x)\n");
+      exit (1);
+    }
+  if (mpfr_sub (x, z, y, GMP_RNDN) >= 0)
+    {
+      fprintf (stderr, "Wrong inexact flag in x=mpfr_sub(z,0) for prec(z)>prec(x)\n");
+      exit (1);
+    }
+
   mpfr_clear (x);
   mpfr_clear (y);
   mpfr_clear (z);