MSVC 2013 compatibility: more workarounds for array initialization bug.

Followup to e2180ee85b.

src/Magnum/Math/RectangularMatrix.h

@@ -673,7 +673,12 @@ namespace Implementation {
 }
 
 #ifndef CORRADE_GCC45_COMPATIBILITY
-template<std::size_t cols, std::size_t rows, class T> template<std::size_t ...sequence> inline constexpr RectangularMatrix<cols, rows, T>::RectangularMatrix(Implementation::Sequence<sequence...>, const Vector<DiagonalSize, T>& diagonal): _data{Implementation::diagonalMatrixColumn<rows, sequence>(sequence < DiagonalSize ? diagonal[sequence] : T{})...} {}
+template<std::size_t cols, std::size_t rows, class T> template<std::size_t ...sequence> inline constexpr RectangularMatrix<cols, rows, T>::RectangularMatrix(Implementation::Sequence<sequence...>, const Vector<DiagonalSize, T>& diagonal): 
+    #ifndef CORRADE_MSVC2013_COMPATIBILITY
+    _data{Implementation::diagonalMatrixColumn<rows, sequence>(sequence < DiagonalSize ? diagonal[sequence] : T{})...} {}
+    #else
+    _data({Implementation::diagonalMatrixColumn<rows, sequence>(sequence < DiagonalSize ? diagonal[sequence] : T{})...}) {}
+    #endif
 #else
 template<std::size_t cols, std::size_t rows, class T> template<std::size_t ...sequence> inline RectangularMatrix<cols, rows, T>::RectangularMatrix(Implementation::Sequence<sequence...>, const Vector<DiagonalSize, T>& diagonal) {
     constructInternal({Implementation::diagonalMatrixColumn<rows, sequence>(sequence < DiagonalSize ? diagonal[sequence] : T{})...});

src/Magnum/Math/Vector.h

@@ -204,8 +204,22 @@ template<std::size_t size, class T> class Vector {
          *
          * @see operator[]()
          */
-        T* data() { return _data; }
+        T* data() {
-        constexpr const T* data() const { return _data; } /**< @overload */
+            #ifndef CORRADE_MSVC2013_COMPATIBILITY
+            return _data;
+            #else
+            return &_data[0];
+            #endif
+        }
+
+        /** @overload */
+        constexpr const T* data() const {
+            #ifndef CORRADE_MSVC2013_COMPATIBILITY
+            return _data;
+            #else
+            return &_data[0];
+            #endif
+        }
 
         /**
          * @brief Value at given position