diff --git a/tests/float/inf_nan_arith.py b/tests/float/inf_nan_arith.py
index d1a6b1887..33cadbf39 100644
--- a/tests/float/inf_nan_arith.py
+++ b/tests/float/inf_nan_arith.py
@@ -3,7 +3,7 @@
 inf = float("inf")
 nan = float("nan")
 
-values = (-2, -1, 0, 1, 2, inf, nan)
+values = (-2, -1, 0, 1, 2, inf, -inf, nan)
 
 for x in values:
     for y in values: