2 files changed, 36 insertions, 0 deletions
diff --git a/libcxx/test/utilities/ratio/ratio.arithmetic/ratio_add.pass.cpp b/libcxx/test/utilities/ratio/ratio.arithmetic/ratio_add.pass.cpp
index 3d43fc04845..a537f0215ca 100644
--- a/libcxx/test/utilities/ratio/ratio.arithmetic/ratio_add.pass.cpp
+++ b/libcxx/test/utilities/ratio/ratio.arithmetic/ratio_add.pass.cpp
@@ -55,4 +55,22 @@ int main()
     typedef std::ratio_add<R1, R2>::type R;
     static_assert(R::num == 127970191639601LL && R::den == 5177331081415LL, "");
     }
+    {
+    typedef std::ratio<0> R1;
+    typedef std::ratio<0> R2;
+    typedef std::ratio_add<R1, R2>::type R;
+    static_assert(R::num == 0 && R::den == 1, "");
+    }
+    {
+    typedef std::ratio<1> R1;
+    typedef std::ratio<0> R2;
+    typedef std::ratio_add<R1, R2>::type R;
+    static_assert(R::num == 1 && R::den == 1, "");
+    }
+    {
+    typedef std::ratio<0> R1;
+    typedef std::ratio<1> R2;
+    typedef std::ratio_add<R1, R2>::type R;
+    static_assert(R::num == 1 && R::den == 1, "");
+    }
 }
diff --git a/libcxx/test/utilities/ratio/ratio.arithmetic/ratio_subtract.pass.cpp b/libcxx/test/utilities/ratio/ratio.arithmetic/ratio_subtract.pass.cpp
index 5c77fffae24..33efd90f555 100644
--- a/libcxx/test/utilities/ratio/ratio.arithmetic/ratio_subtract.pass.cpp
+++ b/libcxx/test/utilities/ratio/ratio.arithmetic/ratio_subtract.pass.cpp
@@ -55,4 +55,22 @@ int main()
     typedef std::ratio_subtract<R1, R2>::type R;
     static_assert(R::num == -126708206685271LL && R::den == 5177331081415LL, "");
     }
+    {
+    typedef std::ratio<0> R1;
+    typedef std::ratio<0> R2;
+    typedef std::ratio_subtract<R1, R2>::type R;
+    static_assert(R::num == 0 && R::den == 1, "");
+    }
+    {
+    typedef std::ratio<1> R1;
+    typedef std::ratio<0> R2;
+    typedef std::ratio_subtract<R1, R2>::type R;
+    static_assert(R::num == 1 && R::den == 1, "");
+    }
+    {
+    typedef std::ratio<0> R1;
+    typedef std::ratio<1> R2;
+    typedef std::ratio_subtract<R1, R2>::type R;
+    static_assert(R::num == -1 && R::den == 1, "");
+    }
 }