Used static_assert for static assertion

Yay for C++11! static_assert is available since GCC 4.3.

Fixed warning when compiling with GCC 4.8:

src/utils/mathutils.cpp:53:18: warning: typedef ‘float_must_be_32_bits’
locally defined but not used [-Wunused-local-typedefs]

1 files changed, 2 insertions, 1 deletions

diff --git a/src/utils/mathutils.cpp b/src/utils/mathutils.cpp
index 6f7bc223..a11538e5 100644
--- a/src/utils/mathutils.cpp
+++ b/src/utils/mathutils.cpp
@@ -50,7 +50,8 @@ namespace math {
  */
 float fastInvSqrt(float x)
 {
-    typedef char float_must_be_32_bits[(sizeof(float) == 4) * 2 - 1];
+    static_assert(sizeof(float) == 4, "float must be 32 bits");
+
     float xhalf = 0.5f * x;
     uint32_t i;
     memcpy(&i, &x, 4);