1 files changed, 5 insertions, 0 deletions
diff --git a/ext/bigdecimal/bigdecimal.c b/ext/bigdecimal/bigdecimal.c
index 636c0907d6..7400b313a4 100644
--- a/ext/bigdecimal/bigdecimal.c
+++ b/ext/bigdecimal/bigdecimal.c
@@ -4345,6 +4345,11 @@ VpMidRound(Real *y, int f, int nf)
     nf += y->exponent*((int)BASE_FIG);
     exptoadd=0;
     if (nf < 0) {
+	/* rounding position too left(large). */
+	if((f!=VP_ROUND_CEIL) && (f!=VP_ROUND_FLOOR)) {
+	    VpSetZero(y,VpGetSign(y)); /* truncate everything */
+	    return 0;
+	}
         exptoadd = -nf;
         nf = 0;
     }