diff --git a/src/libCom/test/epicsCalcTest.cpp b/src/libCom/test/epicsCalcTest.cpp
index d7836a338..3fee4923b 100644
--- a/src/libCom/test/epicsCalcTest.cpp
+++ b/src/libCom/test/epicsCalcTest.cpp
@@ -553,10 +553,18 @@ MAIN(epicsCalcTest)
     testExpr(0.0 + NaN);
     testExpr(Inf + 0.0);
     testExpr(Inf + Inf);
+#if defined(_WIN64) && defined(_MSC_VER)
+    testCalc("Inf + -Inf", NaN);
+#else
     testExpr(Inf + -Inf);
+#endif
     testExpr(Inf + NaN);
     testExpr(-Inf + 0.0);
+#if defined(_WIN64) && defined(_MSC_VER)
+    testCalc("-Inf + Inf", NaN);
+#else
     testExpr(-Inf + Inf);
+#endif
     testExpr(-Inf + -Inf);
     testExpr(-Inf + NaN);
     testExpr(NaN + 0.0);