From 90b519c4d2493baf68f17b609112f8f5ce346b21 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Vladim=C3=ADr=20Vondru=C5=A1?= <mosra@centrum.cz>
Date: Sat, 17 Jan 2015 14:04:47 +0100
Subject: [PATCH] Math: improve Constants test, fix Clang compilation.

---
 src/Magnum/Math/Test/ConstantsTest.cpp | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/src/Magnum/Math/Test/ConstantsTest.cpp b/src/Magnum/Math/Test/ConstantsTest.cpp
index 2dc02c581..e68626dd9 100644
--- a/src/Magnum/Math/Test/ConstantsTest.cpp
+++ b/src/Magnum/Math/Test/ConstantsTest.cpp
@@ -23,6 +23,7 @@
     DEALINGS IN THE SOFTWARE.
 */
 
+#include <cmath>
 #include <Corrade/TestSuite/Tester.h>
 
 #include "Magnum/Math/Constants.h"
@@ -77,10 +78,15 @@ template<class T> void ConstantsTest::_constants() {
 }
 
 template<class T> void ConstantsTest::_specials() {
-    constexpr T g = Constants<T>::nan();
-    CORRADE_VERIFY(g != g);
+    constexpr T a = Constants<T>::nan();
+    CORRADE_VERIFY(std::isnan(a));
+    CORRADE_VERIFY(a != a);
 
-    constexpr T h = Constants<T>::inf() - Constants<T>::inf();
+    constexpr T b = Constants<T>::inf();
+    CORRADE_VERIFY(std::isinf(b));
+
+    /* Clang complains that producing NaN is not constexpr */
+    T h = Constants<T>::inf() - Constants<T>::inf();
     CORRADE_VERIFY(h != h);
 }