1 files changed, 9 insertions, 1 deletions

diff --git a/bignum.c b/bignum.c
index cba4210946..bb6430c19d 100644
--- a/bignum.c
+++ b/bignum.c
@@ -1280,7 +1280,15 @@ rb_big_cmp(VALUE x, VALUE y)
 	break;
 
       case T_FLOAT:
-	return rb_dbl_cmp(rb_big2dbl(x), RFLOAT_VALUE(y));
+	{
+	    double a = RFLOAT_VALUE(y);
+
+	    if (isinf(a)) {
+		if (a > 0.0) return INT2FIX(-1);
+		else return INT2FIX(1);
+	    }
+	    return rb_dbl_cmp(rb_big2dbl(x), a);
+	}
 
       default:
 	return rb_num_coerce_cmp(x, y, rb_intern("<=>"));