Merge to upstream r225300.

Change-Id: I2b23715db9ac129ff80aa78ad5824db0a4d6fbb3

test/std/numerics/c.math/cmath_isinf.pass.cpp

@@ -0,0 +1,30 @@
+//===----------------------------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+// <cmath>
+
+// isinf
+
+// XFAIL: linux
+
+#include <cmath>
+#include <type_traits>
+#include <cassert>
+
+int main()
+{
+#ifdef isinf
+#error isinf defined
+#endif
+    static_assert((std::is_same<decltype(std::isinf((float)0)), bool>::value), "");
+    static_assert((std::is_same<decltype(std::isinf((double)0)), bool>::value), "");
+    static_assert((std::is_same<decltype(std::isinf(0)), bool>::value), "");
+    static_assert((std::is_same<decltype(std::isinf((long double)0)), bool>::value), "");
+    assert(std::isinf(-1.0) == false);
+}