MSVC 2015 Update 1: fixed nearly all constexpr bugs.

src/Magnum/Array.h

@@ -77,11 +77,7 @@ template<UnsignedInt dimensions, class T> class Array {
         constexpr /*implicit*/ Array(T value);
         #else
         template<class U, class V = typename std::enable_if<std::is_same<T, U>::value && dimensions != 1, T>::type>
-        #ifndef CORRADE_MSVC2015_COMPATIBILITY
+        constexpr /*implicit*/ Array(U value): Array(typename Math::Implementation::GenerateSequence<dimensions>::Type(), value) {}
-        /* Can't use delegating constructors with constexpr -- https://connect.microsoft.com/VisualStudio/feedback/details/1579279/c-constexpr-does-not-work-with-delegating-constructors */
-        constexpr
-        #endif
-        /*implicit*/ Array(U value): Array(typename Math::Implementation::GenerateSequence<dimensions>::Type(), value) {}
         #endif
 
         /** @brief Equality */

src/Magnum/ImageView.h

@@ -108,11 +108,7 @@ template<UnsignedInt dimensions> class ImageView {
         /** @overload
          * Similar to the above, but uses default @ref PixelStorage parameters.
          */
-        #ifndef CORRADE_MSVC2015_COMPATIBILITY
+        constexpr explicit ImageView(PixelFormat format, PixelType type, const VectorTypeFor<dimensions, Int>& size) noexcept: ImageView{{}, format, type, size} {}
-        /* Can't use delegating constructors with constexpr -- https://connect.microsoft.com/VisualStudio/feedback/details/1579279/c-constexpr-does-not-work-with-delegating-constructors */
-        constexpr
-        #endif
-        explicit ImageView(PixelFormat format, PixelType type, const VectorTypeFor<dimensions, Int>& size) noexcept: ImageView{{}, format, type, size} {}
 
         /** @brief Storage of pixel data */
         PixelStorage storage() const { return _storage; }
@@ -241,11 +237,7 @@ template<UnsignedInt dimensions> class CompressedImageView {
          * Similar the above, but uses default @ref CompressedPixelStorage
          * parameters (or the hardcoded ones in OpenGL ES and WebGL).
          */
-        #if !defined(CORRADE_MSVC2015_COMPATIBILITY) || defined(MAGNUM_TARGET_GLES)
+        constexpr explicit CompressedImageView(CompressedPixelFormat format, const VectorTypeFor<dimensions, Int>& size, Containers::ArrayView<const void> data) noexcept;
-        /* Can't use delegating constructors with constexpr -- https://connect.microsoft.com/VisualStudio/feedback/details/1579279/c-constexpr-does-not-work-with-delegating-constructors */
-        constexpr
-        #endif
-        explicit CompressedImageView(CompressedPixelFormat format, const VectorTypeFor<dimensions, Int>& size, Containers::ArrayView<const void> data) noexcept;
 
         #ifndef MAGNUM_TARGET_GLES
         /**
@@ -364,12 +356,7 @@ template<UnsignedInt dimensions> constexpr CompressedImageView<dimensions>::Comp
     _format{format}, _size{size} {}
 
 #ifndef MAGNUM_TARGET_GLES
-template<UnsignedInt dimensions>
+template<UnsignedInt dimensions> constexpr CompressedImageView<dimensions>::CompressedImageView(const CompressedPixelFormat format, const VectorTypeFor<dimensions, Int>& size, const Containers::ArrayView<const void> data) noexcept: CompressedImageView{{}, format, size, data} {}
-#ifndef CORRADE_MSVC2015_COMPATIBILITY
-/* Can't use delegating constructors with constexpr -- https://connect.microsoft.com/VisualStudio/feedback/details/1579279/c-constexpr-does-not-work-with-delegating-constructors */
-constexpr
-#endif
-CompressedImageView<dimensions>::CompressedImageView(const CompressedPixelFormat format, const VectorTypeFor<dimensions, Int>& size, const Containers::ArrayView<const void> data) noexcept: CompressedImageView{{}, format, size, data} {}
 
 template<UnsignedInt dimensions> constexpr CompressedImageView<dimensions>::CompressedImageView(const CompressedPixelFormat format, const VectorTypeFor<dimensions, Int>& size) noexcept: CompressedImageView{{}, format, size} {}
 #endif

src/Magnum/Math/BoolVector.h

@@ -93,12 +93,7 @@ template<std::size_t size> class BoolVector {
         #ifdef DOXYGEN_GENERATING_OUTPUT
         inline explicit BoolVector(T value);
         #else
-        template<class T, class U = typename std::enable_if<std::is_same<bool, T>::value && size != 1, bool>::type>
+        template<class T, class U = typename std::enable_if<std::is_same<bool, T>::value && size != 1, bool>::type> constexpr explicit BoolVector(T value): BoolVector(typename Implementation::GenerateSequence<DataSize>::Type(), value ? FullSegmentMask : 0) {}
-        #ifndef CORRADE_MSVC2015_COMPATIBILITY
-        /* Can't use delegating constructors with constexpr -- https://connect.microsoft.com/VisualStudio/feedback/details/1579279/c-constexpr-does-not-work-with-delegating-constructors */
-        constexpr
-        #endif
-        explicit BoolVector(T value): BoolVector(typename Implementation::GenerateSequence<DataSize>::Type(), value ? FullSegmentMask : 0) {}
         #endif
 
         /** @brief Copy constructor */

src/Magnum/Math/Complex.h

@@ -178,12 +178,7 @@ template<class T> class Complex {
         template<class U> constexpr explicit Complex(const Complex<U>& other): _real{T(other._real)}, _imaginary{T(other._imaginary)} {}
 
         /** @brief Construct complex number from external representation */
-        template<class U, class V = decltype(Implementation::ComplexConverter<T, U>::from(std::declval<U>()))>
+        template<class U, class V = decltype(Implementation::ComplexConverter<T, U>::from(std::declval<U>()))> constexpr explicit Complex(const U& other): Complex{Implementation::ComplexConverter<T, U>::from(other)} {}
-        #ifndef CORRADE_MSVC2015_COMPATIBILITY
-        /* Can't use delegating constructors with constexpr -- https://connect.microsoft.com/VisualStudio/feedback/details/1579279/c-constexpr-does-not-work-with-delegating-constructors */
-        constexpr
-        #endif
-        explicit Complex(const U& other): Complex{Implementation::ComplexConverter<T, U>::from(other)} {}
 
         /** @brief Convert complex number to external representation */
         template<class U, class V = decltype(Implementation::ComplexConverter<T, U>::to(std::declval<Complex<T>>()))> constexpr explicit operator U() const {

src/Magnum/Math/DualComplex.h

@@ -163,12 +163,7 @@ template<class T> class DualComplex: public Dual<Complex<T>> {
             {}
 
         /** @brief Construct dual complex number from external representation */
-        template<class U, class V = decltype(Implementation::DualComplexConverter<T, U>::from(std::declval<U>()))>
+        template<class U, class V = decltype(Implementation::DualComplexConverter<T, U>::from(std::declval<U>()))> constexpr explicit DualComplex(const U& other): DualComplex{Implementation::DualComplexConverter<T, U>::from(other)} {}
-        #ifndef CORRADE_MSVC2015_COMPATIBILITY
-        /* Can't use delegating constructors with constexpr -- https://connect.microsoft.com/VisualStudio/feedback/details/1579279/c-constexpr-does-not-work-with-delegating-constructors */
-        constexpr
-        #endif
-        explicit DualComplex(const U& other): DualComplex{Implementation::DualComplexConverter<T, U>::from(other)} {}
 
         /** @brief Copy constructor */
         constexpr DualComplex(const Dual<Complex<T>>& other): Dual<Complex<T>>(other) {}

src/Magnum/Math/DualQuaternion.h

@@ -234,12 +234,7 @@ template<class T> class DualQuaternion: public Dual<Quaternion<T>> {
         template<class U> constexpr explicit DualQuaternion(const DualQuaternion<U>& other): Dual<Quaternion<T>>(other) {}
 
         /** @brief Construct dual quaternion from external representation */
-        template<class U, class V = decltype(Implementation::DualQuaternionConverter<T, U>::from(std::declval<U>()))>
+        template<class U, class V = decltype(Implementation::DualQuaternionConverter<T, U>::from(std::declval<U>()))> constexpr explicit DualQuaternion(const U& other): DualQuaternion{Implementation::DualQuaternionConverter<T, U>::from(other)} {}
-        #ifndef CORRADE_MSVC2015_COMPATIBILITY
-        /* Can't use delegating constructors with constexpr -- https://connect.microsoft.com/VisualStudio/feedback/details/1579279/c-constexpr-does-not-work-with-delegating-constructors */
-        constexpr
-        #endif
-        explicit DualQuaternion(const U& other): DualQuaternion{Implementation::DualQuaternionConverter<T, U>::from(other)} {}
 
         /** @brief Copy constructor */
         constexpr DualQuaternion(const Dual<Quaternion<T>>& other): Dual<Quaternion<T>>(other) {}

src/Magnum/Math/Matrix.h

@@ -132,14 +132,7 @@ template<std::size_t size, class T> class Matrix: public RectangularMatrix<size,
          * // integral == {{1, 2}, {-15, 7}}
          * @endcode
          */
-        template<class U> constexpr explicit Matrix(const RectangularMatrix<size, size, U>& other):
+        template<class U> constexpr explicit Matrix(const RectangularMatrix<size, size, U>& other): RectangularMatrix<size, size, T>(other) {}
-            #ifndef CORRADE_MSVC2015_COMPATIBILITY
-            RectangularMatrix<size, size, T>(other)
-            #else
-            /* Avoid using non-constexpr version */
-            RectangularMatrix<size, size, T>(typename Implementation::GenerateSequence<size>::Type(), other)
-            #endif
-        {}
 
         /** @brief Construct matrix from external representation */
         template<class U, class V = decltype(Implementation::RectangularMatrixConverter<size, size, T, U>::from(std::declval<U>()))> constexpr explicit Matrix(const U& other): RectangularMatrix<size, size, T>(Implementation::RectangularMatrixConverter<size, size, T, U>::from(other)) {}

src/Magnum/Math/Matrix3.h

@@ -162,15 +162,8 @@ template<class T> class Matrix3: public Matrix3x3<T> {
         constexpr /*implicit*/ Matrix3(IdentityInitT = IdentityInit, T value = T{1})
             /** @todoc remove workaround when doxygen is sane */
             #ifndef DOXYGEN_GENERATING_OUTPUT
-            #ifndef CORRADE_MSVC2015_COMPATIBILITY
+            /* MSVC 2015 can't handle {} here */
-            : Matrix3x3<T>{IdentityInit, value}
+            : Matrix3x3<T>(IdentityInit, value)
-            #else
-            /* Avoid using non-constexpr version, also MSVC 2015 can't handle
-               {} here */
-            : Matrix3x3<T>(Vector<3, T>{value, T(0), T(0)},
-                           Vector<3, T>{T(0), value, T(0)},
-                           Vector<3, T>{T(0), T(0), value})
-            #endif
             #endif
             {}
 
@@ -178,15 +171,8 @@ template<class T> class Matrix3: public Matrix3x3<T> {
         constexpr explicit Matrix3(ZeroInitT)
             /** @todoc remove workaround when doxygen is sane */
             #ifndef DOXYGEN_GENERATING_OUTPUT
-            #ifndef CORRADE_MSVC2015_COMPATIBILITY
+            /* MSVC 2015 can't handle {} here */
             : Matrix3x3<T>(ZeroInit)
-            #else
-            /* Avoid using non-constexpr version, also MSVC 2015 can't handle
-               {} here */
-            : Matrix3x3<T>(Vector<3, T>{T(0), T(0), T(0)},
-                           Vector<3, T>{T(0), T(0), T(0)},
-                           Vector<3, T>{T(0), T(0), T(0)})
-            #endif
             #endif
             {}
 

src/Magnum/Math/Matrix4.h

@@ -258,16 +258,8 @@ template<class T> class Matrix4: public Matrix4x4<T> {
         constexpr /*implicit*/ Matrix4(IdentityInitT = IdentityInit, T value = T{1})
             /** @todoc remove workaround when doxygen is sane */
             #ifndef DOXYGEN_GENERATING_OUTPUT
-            #ifndef CORRADE_MSVC2015_COMPATIBILITY
+            /* MSVC 2015 can't handle {} here */
-            : Matrix4x4<T>{IdentityInit, value}
+            : Matrix4x4<T>(IdentityInit, value)
-            #else
-            /* Avoid using non-constexpr version, also MSVC 2015 can't handle
-               {} here */
-            : Matrix4x4<T>(Vector<4, T>{value, T(0), T(0), T(0)},
-                           Vector<4, T>{T(0), value, T(0), T(0)},
-                           Vector<4, T>{T(0), T(0), value, T(0)},
-                           Vector<4, T>{T(0), T(0), T(0), value})
-            #endif
             #endif
             {}
 
@@ -275,16 +267,8 @@ template<class T> class Matrix4: public Matrix4x4<T> {
         constexpr explicit Matrix4(ZeroInitT)
             /** @todoc remove workaround when doxygen is sane */
             #ifndef DOXYGEN_GENERATING_OUTPUT
-            #ifndef CORRADE_MSVC2015_COMPATIBILITY
+            /* MSVC 2015 can't handle {} here */
             : Matrix4x4<T>(ZeroInit)
-            #else
-            /* Avoid using non-constexpr version, also MSVC 2015 can't handle
-               {} here */
-            : Matrix4x4<T>(Vector<4, T>{T(0), T(0), T(0), T(0)},
-                           Vector<4, T>{T(0), T(0), T(0), T(0)},
-                           Vector<4, T>{T(0), T(0), T(0), T(0)},
-                           Vector<4, T>{T(0), T(0), T(0), T(0)})
-            #endif
             #endif
             {}
 

src/Magnum/Math/Quaternion.h

@@ -241,12 +241,7 @@ template<class T> class Quaternion {
         template<class U> constexpr explicit Quaternion(const Quaternion<U>& other): _vector{other._vector}, _scalar{T(other._scalar)} {}
 
         /** @brief Construct quaternion from external representation */
-        template<class U, class V = decltype(Implementation::QuaternionConverter<T, U>::from(std::declval<U>()))>
+        template<class U, class V = decltype(Implementation::QuaternionConverter<T, U>::from(std::declval<U>()))> constexpr explicit Quaternion(const U& other): Quaternion{Implementation::QuaternionConverter<T, U>::from(other)} {}
-        #ifndef CORRADE_MSVC2015_COMPATIBILITY
-        /* Can't use delegating constructors with constexpr -- https://connect.microsoft.com/VisualStudio/feedback/details/1579279/c-constexpr-does-not-work-with-delegating-constructors */
-        constexpr
-        #endif
-        explicit Quaternion(const U& other): Quaternion{Implementation::QuaternionConverter<T, U>::from(other)} {}
 
         /** @brief Convert quaternion to external representation */
         template<class U, class V = decltype(Implementation::QuaternionConverter<T, U>::to(std::declval<Quaternion<T>>()))> constexpr explicit operator U() const {

src/Magnum/Math/Range.h

@@ -99,12 +99,7 @@ template<UnsignedInt dimensions, class T> class Range {
         template<class U> constexpr explicit Range(const Range<dimensions, U>& other): _min(other._min), _max(other._max) {}
 
         /** @brief Construct range from external representation */
-        template<class U, class V = decltype(Implementation::RangeConverter<dimensions, T, U>::from(std::declval<U>()))>
+        template<class U, class V = decltype(Implementation::RangeConverter<dimensions, T, U>::from(std::declval<U>()))> constexpr explicit Range(const U& other): Range{Implementation::RangeConverter<dimensions, T, U>::from(other)} {}
-        #ifndef CORRADE_MSVC2015_COMPATIBILITY
-        /* Can't use delegating constructors with constexpr -- https://connect.microsoft.com/VisualStudio/feedback/details/1579279/c-constexpr-does-not-work-with-delegating-constructors */
-        constexpr
-        #endif
-        explicit Range(const U& other): Range{Implementation::RangeConverter<dimensions, T, U>::from(other)} {}
 
         /** @brief Convert range to external representation */
         template<class U, class V = decltype(Implementation::RangeConverter<dimensions, T, U>::to(std::declval<Range<dimensions, T>>()))> constexpr explicit operator U() const {

src/Magnum/Math/RectangularMatrix.h

@@ -57,11 +57,6 @@ template<std::size_t cols, std::size_t rows, class T> class RectangularMatrix {
 
     template<std::size_t, std::size_t, class> friend class RectangularMatrix;
 
-    #ifdef CORRADE_MSVC2015_COMPATIBILITY
-    /* Delegating constexpr constructor workarounds */
-    friend class Matrix<cols, T>;
-    #endif
-
     public:
         typedef T Type;         /**< @brief Underlying data type */
 
@@ -113,12 +108,7 @@ template<std::size_t cols, std::size_t rows, class T> class RectangularMatrix {
         }
 
         /** @brief Construct zero-filled matrix */
-        /** @todo Remove MSVC workaround when fixed */
+        constexpr /*implicit*/ RectangularMatrix(ZeroInitT = ZeroInit)
-        #ifndef CORRADE_MSVC2015_COMPATIBILITY
-        /* Can't use delegating constructors with constexpr -- https://connect.microsoft.com/VisualStudio/feedback/details/1579279/c-constexpr-does-not-work-with-delegating-constructors */
-        constexpr
-        #endif
-        /*implicit*/ RectangularMatrix(ZeroInitT = ZeroInit)
             /** @todoc remove workaround when doxygen is sane */
             #ifndef DOXYGEN_GENERATING_OUTPUT
             /* MSVC 2015 can't handle {} here */
@@ -157,20 +147,10 @@ template<std::size_t cols, std::size_t rows, class T> class RectangularMatrix {
          * // integral == {1, 2, -15, 7}
          * @endcode
          */
-        template<class U>
+        template<class U> constexpr explicit RectangularMatrix(const RectangularMatrix<cols, rows, U>& other): RectangularMatrix(typename Implementation::GenerateSequence<cols>::Type(), other) {}
-        #ifndef CORRADE_MSVC2015_COMPATIBILITY
-        /* Can't use delegating constructors with constexpr -- https://connect.microsoft.com/VisualStudio/feedback/details/1579279/c-constexpr-does-not-work-with-delegating-constructors */
-        constexpr
-        #endif
-        explicit RectangularMatrix(const RectangularMatrix<cols, rows, U>& other): RectangularMatrix(typename Implementation::GenerateSequence<cols>::Type(), other) {}
 
         /** @brief Construct matrix from external representation */
-        template<class U, class V = decltype(Implementation::RectangularMatrixConverter<cols, rows, T, U>::from(std::declval<U>()))>
+        template<class U, class V = decltype(Implementation::RectangularMatrixConverter<cols, rows, T, U>::from(std::declval<U>()))> constexpr explicit RectangularMatrix(const U& other): RectangularMatrix(Implementation::RectangularMatrixConverter<cols, rows, T, U>::from(other)) {}
-        #ifndef CORRADE_MSVC2015_COMPATIBILITY
-        /* Can't use delegating constructors with constexpr -- https://connect.microsoft.com/VisualStudio/feedback/details/1579279/c-constexpr-does-not-work-with-delegating-constructors */
-        constexpr
-        #endif
-        explicit RectangularMatrix(const U& other): RectangularMatrix(Implementation::RectangularMatrixConverter<cols, rows, T, U>::from(other)) {}
 
         /** @brief Copy constructor */
         constexpr RectangularMatrix(const RectangularMatrix<cols, rows, T>&) = default;

src/Magnum/Math/Test/BoolVectorTest.cpp

@@ -99,18 +99,10 @@ void BoolVectorTest::constructNoInit() {
 }
 
 void BoolVectorTest::constructOneValue() {
-    #ifndef CORRADE_MSVC2015_COMPATIBILITY
+    constexpr BoolVector19 a(false);
-    /* Can't use delegating constructors with constexpr -- https://connect.microsoft.com/VisualStudio/feedback/details/1579279/c-constexpr-does-not-work-with-delegating-constructors */
-    constexpr
-    #endif
-    BoolVector19 a(false);
     CORRADE_COMPARE(a, BoolVector19(0x00, 0x00, 0x00));
 
-    #ifndef CORRADE_MSVC2015_COMPATIBILITY
+    constexpr BoolVector19 b(true);
-    /* Can't use delegating constructors with constexpr -- https://connect.microsoft.com/VisualStudio/feedback/details/1579279/c-constexpr-does-not-work-with-delegating-constructors */
-    constexpr
-    #endif
-    BoolVector19 b(true);
     CORRADE_COMPARE(b, BoolVector19(0xff, 0xff, 0x07));
 
     CORRADE_VERIFY(!(std::is_convertible<bool, BoolVector19>::value));

src/Magnum/Math/Test/ComplexTest.cpp

@@ -201,19 +201,14 @@ void ComplexTest::convert() {
 
     /* GCC 5.1 fills the result with zeros instead of properly calling
        delegated copy constructor if using constexpr. Reported here:
-       https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66450
+       https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66450 */
-       MSVC 2015: Can't use delegating constructors with constexpr:
+    #if !defined(__GNUC__) || defined(__clang__)
-       https://connect.microsoft.com/VisualStudio/feedback/details/1579279/c-constexpr-does-not-work-with-delegating-constructors */
-    #if (!defined(__GNUC__) || defined(__clang__)) && !defined(CORRADE_MSVC2015_COMPATIBILITY)
     constexpr
     #endif
     Complex c(a);
     CORRADE_COMPARE(c, b);
 
-    #ifndef CORRADE_MSVC2015_COMPATIBILITY /* Why can't be conversion constexpr? */
+    constexpr Cmpl d(b);
-    constexpr
-    #endif
-    Cmpl d(b);
     CORRADE_COMPARE(d.re, a.re);
     CORRADE_COMPARE(d.im, a.im);
 

src/Magnum/Math/Test/DualComplexTest.cpp

@@ -198,19 +198,14 @@ void DualComplexTest::convert() {
 
     /* GCC 5.1 fills the result with zeros instead of properly calling
        delegated copy constructor if using constexpr. Reported here:
-       https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66450
+       https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66450 */
-       MSVC 2015: Can't use delegating constructors with constexpr:
+    #if !defined(__GNUC__) || defined(__clang__)
-       https://connect.microsoft.com/VisualStudio/feedback/details/1579279/c-constexpr-does-not-work-with-delegating-constructors */
-    #if (!defined(__GNUC__) || defined(__clang__)) && !defined(CORRADE_MSVC2015_COMPATIBILITY)
     constexpr
     #endif
     DualComplex c{a};
     CORRADE_COMPARE(c, b);
 
-    #ifndef CORRADE_MSVC2015_COMPATIBILITY /* Why can't be conversion constexpr? */
+    constexpr DualCmpl d(b);
-    constexpr
-    #endif
-    DualCmpl d(b);
     CORRADE_COMPARE(d.re, a.re);
     CORRADE_COMPARE(d.im, a.im);
     CORRADE_COMPARE(d.x, a.x);

src/Magnum/Math/Test/DualQuaternionTest.cpp

@@ -216,19 +216,14 @@ void DualQuaternionTest::convert() {
 
     /* GCC 5.1 fills the result with zeros instead of properly calling
        delegated copy constructor if using constexpr. Reported here:
-       https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66450
+       https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66450 */
-       MSVC 2015: Can't use delegating constructors with constexpr:
+    #if !defined(__GNUC__) || defined(__clang__)
-       https://connect.microsoft.com/VisualStudio/feedback/details/1579279/c-constexpr-does-not-work-with-delegating-constructors */
-    #if (!defined(__GNUC__) || defined(__clang__)) && !defined(CORRADE_MSVC2015_COMPATIBILITY)
     constexpr
     #endif
     DualQuaternion c{a};
     CORRADE_COMPARE(c, b);
 
-    #ifndef CORRADE_MSVC2015_COMPATIBILITY /* Why can't be conversion constexpr? */
+    constexpr DualQuat d(b);
-    constexpr
-    #endif
-    DualQuat d(b);
     CORRADE_COMPARE(d.re.x, a.re.x);
     CORRADE_COMPARE(d.re.y, a.re.y);
     CORRADE_COMPARE(d.re.z, a.re.z);

src/Magnum/Math/Test/MatrixTest.cpp

@@ -126,21 +126,9 @@ void MatrixTest::construct() {
 }
 
 void MatrixTest::constructIdentity() {
-    #ifndef CORRADE_MSVC2015_COMPATIBILITY
+    constexpr Matrix4x4 identity;
-    /* Can't use delegating constructors with constexpr -- https://connect.microsoft.com/VisualStudio/feedback/details/1579279/c-constexpr-does-not-work-with-delegating-constructors */
+    constexpr Matrix4x4 identity2{IdentityInit};
-    constexpr
+    constexpr Matrix4x4 identity3{IdentityInit, 4.0f};
-    #endif
-    Matrix4x4 identity;
-    #ifndef CORRADE_MSVC2015_COMPATIBILITY
-    /* Can't use delegating constructors with constexpr -- https://connect.microsoft.com/VisualStudio/feedback/details/1579279/c-constexpr-does-not-work-with-delegating-constructors */
-    constexpr
-    #endif
-    Matrix4x4 identity2{IdentityInit};
-    #ifndef CORRADE_MSVC2015_COMPATIBILITY
-    /* Can't use delegating constructors with constexpr -- https://connect.microsoft.com/VisualStudio/feedback/details/1579279/c-constexpr-does-not-work-with-delegating-constructors */
-    constexpr
-    #endif
-    Matrix4x4 identity3{IdentityInit, 4.0f};
 
     Matrix4x4 identityExpected(Vector4(1.0f, 0.0f, 0.0f, 0.0f),
                                Vector4(0.0f, 1.0f, 0.0f, 0.0f),
@@ -158,11 +146,7 @@ void MatrixTest::constructIdentity() {
 }
 
 void MatrixTest::constructZero() {
-    #ifndef CORRADE_MSVC2015_COMPATIBILITY
+    constexpr Matrix4x4 a{ZeroInit};
-    /* Can't use delegating constructors with constexpr -- https://connect.microsoft.com/VisualStudio/feedback/details/1579279/c-constexpr-does-not-work-with-delegating-constructors */
-    constexpr
-    #endif
-    Matrix4x4 a{ZeroInit};
     CORRADE_COMPARE(a, Matrix4x4(Vector4(0.0f, 0.0f, 0.0f, 0.0f),
                                  Vector4(0.0f, 0.0f, 0.0f, 0.0f),
                                  Vector4(0.0f, 0.0f, 0.0f, 0.0f),
@@ -222,10 +206,7 @@ void MatrixTest::convert() {
     constexpr Matrix3x3 c(b);
     CORRADE_COMPARE(c, b);
 
-    #ifndef CORRADE_MSVC2015_COMPATIBILITY /* Why can't be conversion constexpr? */
+    constexpr Mat3 d(b);
-    constexpr
-    #endif
-    Mat3 d(b);
     for(std::size_t i = 0; i != 9; ++i)
         CORRADE_COMPARE(d.a[i], a.a[i]);
 

src/Magnum/Math/Test/QuaternionTest.cpp

@@ -202,19 +202,14 @@ void QuaternionTest::convert() {
 
     /* GCC 5.1 fills the result with zeros instead of properly calling
        delegated copy constructor if using constexpr. Reported here:
-       https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66450
+       https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66450 */
-       MSVC 2015: Can't use delegating constructors with constexpr:
+    #if !defined(__GNUC__) || defined(__clang__)
-       https://connect.microsoft.com/VisualStudio/feedback/details/1579279/c-constexpr-does-not-work-with-delegating-constructors */
-    #if (!defined(__GNUC__) || defined(__clang__)) && !defined(CORRADE_MSVC2015_COMPATIBILITY)
     constexpr
     #endif
     Quaternion c{a};
     CORRADE_COMPARE(c, b);
 
-    #ifndef CORRADE_MSVC2015_COMPATIBILITY /* Why can't be conversion constexpr? */
+    constexpr Quat d(b);
-    constexpr
-    #endif
-    Quat d(b);
     CORRADE_COMPARE(d.x, a.x);
     CORRADE_COMPARE(d.y, a.y);
     CORRADE_COMPARE(d.z, a.z);

src/Magnum/Math/Test/RangeTest.cpp

@@ -215,11 +215,7 @@ void RangeTest::constructConversion() {
     constexpr Range2D b({1.3f, 2.7f}, {-15.0f, 7.0f});
     constexpr Range3D c({1.3f, 2.7f, -1.5f}, {-15.0f, 7.0f, 0.3f});
 
-    #ifndef CORRADE_MSVC2015_COMPATIBILITY
+    constexpr Range1Di d(a);
-    /* Can't use delegating constructors with constexpr -- https://connect.microsoft.com/VisualStudio/feedback/details/1579279/c-constexpr-does-not-work-with-delegating-constructors */
-    constexpr
-    #endif
-    Range1Di d(a);
     CORRADE_COMPARE(d, Range1Di(1, -15));
 
     constexpr Range2Di e(b);
@@ -260,14 +256,12 @@ void RangeTest::convert() {
 
     /* GCC 5.1 fills the result with zeros instead of properly calling
        delegated copy constructor if using constexpr. Reported here:
-       https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66450
+       https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66450 */
-       MSVC 2015: Can't use delegating constructors with constexpr:
+    #if !defined(__GNUC__) || defined(__clang__)
-       https://connect.microsoft.com/VisualStudio/feedback/details/1579279/c-constexpr-does-not-work-with-delegating-constructors */
-    #if (!defined(__GNUC__) || defined(__clang__)) && !defined(CORRADE_MSVC2015_COMPATIBILITY)
     constexpr
     #endif
     Range<2, Float> g{b};
-    #if (!defined(__GNUC__) || defined(__clang__)) && !defined(CORRADE_MSVC2015_COMPATIBILITY)
+    #if !defined(__GNUC__) || defined(__clang__)
     constexpr
     #endif
     Range1D h{a};
@@ -284,26 +278,17 @@ void RangeTest::convert() {
     CORRADE_COMPARE(i, e);
     CORRADE_COMPARE(j, f);
 
-    #ifndef CORRADE_MSVC2015_COMPATIBILITY /* Why can't be conversion constexpr? */
+    constexpr Dim k(d);
-    constexpr
-    #endif
-    Dim k(d);
     CORRADE_COMPARE(k.offset, a.offset);
     CORRADE_COMPARE(k.size, a.size);
 
-    #ifndef CORRADE_MSVC2015_COMPATIBILITY /* Why can't be conversion constexpr? */
+    constexpr Rect l(e);
-    constexpr
-    #endif
-    Rect l(e);
     CORRADE_COMPARE(l.x, b.x);
     CORRADE_COMPARE(l.y, b.y);
     CORRADE_COMPARE(l.w, b.w);
     CORRADE_COMPARE(l.h, b.h);
 
-    #ifndef CORRADE_MSVC2015_COMPATIBILITY /* Why can't be conversion constexpr? */
+    constexpr Box m(f);
-    constexpr
-    #endif
-    Box m(f);
     CORRADE_COMPARE(m.x, c.x);
     CORRADE_COMPARE(m.y, c.y);
     CORRADE_COMPARE(m.z, c.z);

src/Magnum/Math/Test/RectangularMatrixTest.cpp

@@ -149,16 +149,8 @@ void RectangularMatrixTest::construct() {
 }
 
 void RectangularMatrixTest::constructDefault() {
-    #ifndef CORRADE_MSVC2015_COMPATIBILITY
+    constexpr Matrix4x3 a;
-    /* Can't use delegating constructors with constexpr -- https://connect.microsoft.com/VisualStudio/feedback/details/1579279/c-constexpr-does-not-work-with-delegating-constructors */
+    constexpr Matrix4x3 b{ZeroInit};
-    constexpr
-    #endif
-    Matrix4x3 a;
-    #ifndef CORRADE_MSVC2015_COMPATIBILITY
-    /* Can't use delegating constructors with constexpr -- https://connect.microsoft.com/VisualStudio/feedback/details/1579279/c-constexpr-does-not-work-with-delegating-constructors */
-    constexpr
-    #endif
-    Matrix4x3 b{ZeroInit};
     CORRADE_COMPARE(a, Matrix4x3(Vector3(0.0f, 0.0f, 0.0f),
                                  Vector3(0.0f, 0.0f, 0.0f),
                                  Vector3(0.0f, 0.0f, 0.0f),
@@ -182,11 +174,7 @@ void RectangularMatrixTest::constructNoInit() {
 void RectangularMatrixTest::constructConversion() {
     constexpr Matrix2x2 a(Vector2(  1.3f, 2.7f),
                           Vector2(-15.0f, 7.0f));
-    #ifndef CORRADE_MSVC2015_COMPATIBILITY
+    constexpr Matrix2x2i b(a);
-    /* Can't use delegating constructors with constexpr -- https://connect.microsoft.com/VisualStudio/feedback/details/1579279/c-constexpr-does-not-work-with-delegating-constructors */
-    constexpr
-    #endif
-    Matrix2x2i b(a);
 
     CORRADE_COMPARE(b, Matrix2x2i(Vector2i(  1, 2),
                                   Vector2i(-15, 7)));
@@ -245,19 +233,14 @@ void RectangularMatrixTest::convert() {
 
     /* GCC 5.1 fills the result with zeros instead of properly calling
        delegated copy constructor if using constexpr. Reported here:
-       https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66450
+       https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66450 */
-       MSVC 2015: Can't use delegating constructors with constexpr:
+    #if !defined(__GNUC__) || defined(__clang__)
-       https://connect.microsoft.com/VisualStudio/feedback/details/1579279/c-constexpr-does-not-work-with-delegating-constructors */
-    #if (!defined(__GNUC__) || defined(__clang__)) && !defined(CORRADE_MSVC2015_COMPATIBILITY)
     constexpr
     #endif
     Matrix2x3 c{a};
     CORRADE_COMPARE(c, b);
 
-    #ifndef CORRADE_MSVC2015_COMPATIBILITY /* Why can't be conversion constexpr? */
+    constexpr Mat2x3 d(b);
-    constexpr
-    #endif
-    Mat2x3 d(b);
     for(std::size_t i = 0; i != 5; ++i)
         CORRADE_COMPARE(d.a[i], a.a[i]);
 

src/Magnum/Math/Test/Vector2Test.cpp

@@ -152,10 +152,7 @@ void Vector2Test::convert() {
     constexpr Vector2 c(a);
     CORRADE_COMPARE(c, b);
 
-    #ifndef CORRADE_MSVC2015_COMPATIBILITY /* Why can't be conversion constexpr? */
+    constexpr Vec2 d(b);
-    constexpr
-    #endif
-    Vec2 d(b);
     CORRADE_COMPARE(d.x, a.x);
     CORRADE_COMPARE(d.y, a.y);
 

src/Magnum/Math/Test/Vector3Test.cpp

@@ -156,10 +156,7 @@ void Vector3Test::convert() {
     constexpr Vector3 c(a);
     CORRADE_COMPARE(c, b);
 
-    #ifndef CORRADE_MSVC2015_COMPATIBILITY /* Why can't be conversion constexpr? */
+    constexpr Vec3 d(b);
-    constexpr
-    #endif
-    Vec3 d(b);
     CORRADE_COMPARE(d.x, a.x);
     CORRADE_COMPARE(d.y, a.y);
     CORRADE_COMPARE(d.z, a.z);

src/Magnum/Math/Test/Vector4Test.cpp

@@ -171,10 +171,7 @@ void Vector4Test::convert() {
     constexpr Vector4 c(a);
     CORRADE_COMPARE(c, b);
 
-    #ifndef CORRADE_MSVC2015_COMPATIBILITY /* Why can't be conversion constexpr? */
+    constexpr Vec4 d(b);
-    constexpr
-    #endif
-    Vec4 d(b);
     CORRADE_COMPARE(d.x, a.x);
     CORRADE_COMPARE(d.y, a.y);
     CORRADE_COMPARE(d.z, a.z);

src/Magnum/Math/Test/VectorTest.cpp

@@ -201,11 +201,7 @@ void VectorTest::constructNoInit() {
 }
 
 void VectorTest::constructOneValue() {
-    #ifndef CORRADE_MSVC2015_COMPATIBILITY
+    constexpr Vector4 a(7.25f);
-    /* Can't use delegating constructors with constexpr -- https://connect.microsoft.com/VisualStudio/feedback/details/1579279/c-constexpr-does-not-work-with-delegating-constructors */
-    constexpr
-    #endif
-    Vector4 a(7.25f);
 
     CORRADE_COMPARE(a, Vector4(7.25f, 7.25f, 7.25f, 7.25f));
 
@@ -223,11 +219,7 @@ void VectorTest::constructOneComponent() {
 
 void VectorTest::constructConversion() {
     constexpr Vector4 a(1.3f, 2.7f, -15.0f, 7.0f);
-    #ifndef CORRADE_MSVC2015_COMPATIBILITY
+    constexpr Vector4i b(a);
-    /* Can't use delegating constructors with constexpr -- https://connect.microsoft.com/VisualStudio/feedback/details/1579279/c-constexpr-does-not-work-with-delegating-constructors */
-    constexpr
-    #endif
-    Vector4i b(a);
 
     CORRADE_COMPARE(b, Vector4i(1, 2, -15, 7));
 
@@ -247,19 +239,14 @@ void VectorTest::convert() {
 
     /* GCC 5.1 fills the result with zeros instead of properly calling
        delegated copy constructor if using constexpr. Reported here:
-       https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66450
+       https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66450 */
-       MSVC 2015: Can't use delegating constructors with constexpr:
+    #if !defined(__GNUC__) || defined(__clang__)
-       https://connect.microsoft.com/VisualStudio/feedback/details/1579279/c-constexpr-does-not-work-with-delegating-constructors */
-    #if (!defined(__GNUC__) || defined(__clang__)) && !defined(CORRADE_MSVC2015_COMPATIBILITY)
     constexpr
     #endif
     Vector3 c{a};
     CORRADE_COMPARE(c, b);
 
-    #ifndef CORRADE_MSVC2015_COMPATIBILITY /* Why can't be conversion constexpr? */
+    constexpr Vec3 d(b);
-    constexpr
-    #endif
-    Vec3 d(b);
     CORRADE_COMPARE(d.x, a.x);
     CORRADE_COMPARE(d.y, a.y);
     CORRADE_COMPARE(d.z, a.z);

src/Magnum/Math/Vector.h

@@ -98,13 +98,6 @@ template<std::size_t size, class T> class Vector {
 
     template<std::size_t, class> friend class Vector;
 
-    #ifdef CORRADE_MSVC2015_COMPATIBILITY
-    /* Delegating constexpr constructor workarounds */
-    friend class Vector2<T>;
-    friend class Vector3<T>;
-    friend class Vector4<T>;
-    #endif
-
     public:
         typedef T Type;         /**< @brief Underlying data type */
 
@@ -188,12 +181,7 @@ template<std::size_t size, class T> class Vector {
         #ifdef DOXYGEN_GENERATING_OUTPUT
         constexpr explicit Vector(T value);
         #else
-        template<class U, class V = typename std::enable_if<std::is_same<T, U>::value && size != 1, T>::type>
+        template<class U, class V = typename std::enable_if<std::is_same<T, U>::value && size != 1, T>::type> constexpr explicit Vector(U value): Vector(typename Implementation::GenerateSequence<size>::Type(), value) {}
-        #ifndef CORRADE_MSVC2015_COMPATIBILITY
-        /* Can't use delegating constructors with constexpr -- https://connect.microsoft.com/VisualStudio/feedback/details/1579279/c-constexpr-does-not-work-with-delegating-constructors */
-        constexpr
-        #endif
-        explicit Vector(U value): Vector(typename Implementation::GenerateSequence<size>::Type(), value) {}
         #endif
 
         /**
@@ -207,20 +195,10 @@ template<std::size_t size, class T> class Vector {
          * // integral == {1, 2, -15, 7}
          * @endcode
          */
-        template<class U>
+        template<class U> constexpr explicit Vector(const Vector<size, U>& other): Vector(typename Implementation::GenerateSequence<size>::Type(), other) {}
-        #ifndef CORRADE_MSVC2015_COMPATIBILITY
-        /* Can't use delegating constructors with constexpr -- https://connect.microsoft.com/VisualStudio/feedback/details/1579279/c-constexpr-does-not-work-with-delegating-constructors */
-        constexpr
-        #endif
-        explicit Vector(const Vector<size, U>& other): Vector(typename Implementation::GenerateSequence<size>::Type(), other) {}
 
         /** @brief Construct vector from external representation */
-        template<class U, class V = decltype(Implementation::VectorConverter<size, T, U>::from(std::declval<U>()))>
+        template<class U, class V = decltype(Implementation::VectorConverter<size, T, U>::from(std::declval<U>()))> constexpr explicit Vector(const U& other): Vector(Implementation::VectorConverter<size, T, U>::from(other)) {}
-        #ifndef CORRADE_MSVC2015_COMPATIBILITY
-        /* Can't use delegating constructors with constexpr -- https://connect.microsoft.com/VisualStudio/feedback/details/1579279/c-constexpr-does-not-work-with-delegating-constructors */
-        constexpr
-        #endif
-        explicit Vector(const U& other): Vector(Implementation::VectorConverter<size, T, U>::from(other)) {}
 
         /** @brief Copy constructor */
         constexpr Vector(const Vector<size, T>&) = default;

src/Magnum/Math/Vector2.h

@@ -130,14 +130,7 @@ template<class T> class Vector2: public Vector<2, T> {
             {}
 
         /** @copydoc Vector::Vector(T) */
-        constexpr explicit Vector2(T value):
+        constexpr explicit Vector2(T value): Vector<2, T>(value) {}
-            #ifndef CORRADE_MSVC2015_COMPATIBILITY
-            Vector<2, T>(value)
-            #else
-            /* Avoid using non-constexpr version */
-            Vector<2, T>(value, value)
-            #endif
-            {}
 
         /**
          * @brief Constructor
@@ -149,14 +142,7 @@ template<class T> class Vector2: public Vector<2, T> {
         constexpr /*implicit*/ Vector2(T x, T y): Vector<2, T>(x, y) {}
 
         /** @copydoc Vector::Vector(const Vector<size, U>&) */
-        template<class U> constexpr explicit Vector2(const Vector<2, U>& other):
+        template<class U> constexpr explicit Vector2(const Vector<2, U>& other): Vector<2, T>(other) {}
-            #ifndef CORRADE_MSVC2015_COMPATIBILITY
-            Vector<2, T>(other)
-            #else
-            /* Avoid using non-constexpr version */
-            Vector<2, T>(typename Implementation::GenerateSequence<2>::Type(), other)
-            #endif
-            {}
 
         /** @brief Construct vector from external representation */
         template<class U, class V =

src/Magnum/Math/Vector3.h

@@ -152,14 +152,7 @@ template<class T> class Vector3: public Vector<3, T> {
             {}
 
         /** @copydoc Vector::Vector(T) */
-        constexpr explicit Vector3(T value):
+        constexpr explicit Vector3(T value): Vector<3, T>(value) {}
-            #ifndef CORRADE_MSVC2015_COMPATIBILITY
-            Vector<3, T>(value)
-            #else
-            /* Avoid using non-constexpr version */
-            Vector<3, T>(value, value, value)
-            #endif
-            {}
 
         /**
          * @brief Constructor
@@ -180,14 +173,7 @@ template<class T> class Vector3: public Vector<3, T> {
         constexpr /*implicit*/ Vector3(const Vector2<T>& xy, T z): Vector<3, T>(xy[0], xy[1], z) {}
 
         /** @copydoc Vector::Vector(const Vector<size, U>&) */
-        template<class U> constexpr explicit Vector3(const Vector<3, U>& other):
+        template<class U> constexpr explicit Vector3(const Vector<3, U>& other): Vector<3, T>(other) {}
-            #ifndef CORRADE_MSVC2015_COMPATIBILITY
-            Vector<3, T>(other)
-            #else
-            /* Avoid using non-constexpr version */
-            Vector<3, T>(typename Implementation::GenerateSequence<3>::Type(), other)
-            #endif
-            {}
 
         /** @brief Construct vector from external representation */
         template<class U, class V =

src/Magnum/Math/Vector4.h

@@ -78,14 +78,7 @@ template<class T> class Vector4: public Vector<4, T> {
             {}
 
         /** @copydoc Vector::Vector(T) */
-        constexpr explicit Vector4(T value):
+        constexpr explicit Vector4(T value): Vector<4, T>(value) {}
-            #ifndef CORRADE_MSVC2015_COMPATIBILITY
-            Vector<4, T>(value)
-            #else
-            /* Avoid using non-constexpr version */
-            Vector<4, T>(value, value, value, value)
-            #endif
-            {}
 
         /**
          * @brief Constructor
@@ -106,14 +99,7 @@ template<class T> class Vector4: public Vector<4, T> {
         constexpr /*implicit*/ Vector4(const Vector3<T>& xyz, T w): Vector<4, T>(xyz[0], xyz[1], xyz[2], w) {}
 
         /** @copydoc Vector::Vector(const Vector<size, U>&) */
-        template<class U> constexpr explicit Vector4(const Vector<4, U>& other):
+        template<class U> constexpr explicit Vector4(const Vector<4, U>& other): Vector<4, T>(other) {}
-            #ifndef CORRADE_MSVC2015_COMPATIBILITY
-            Vector<4, T>(other)
-            #else
-            /* Avoid using non-constexpr version */
-            Vector<4, T>(typename Implementation::GenerateSequence<4>::Type(), other)
-            #endif
-            {}
 
         /** @brief Construct vector from external representation */
         template<class U, class V = decltype(Implementation::VectorConverter<4, T, U>::from(std::declval<U>()))> constexpr explicit Vector4(const U& other): Vector<4, T>(Implementation::VectorConverter<4, T, U>::from(other)) {}

src/Magnum/Test/ArrayTest.cpp

@@ -51,11 +51,7 @@ void ArrayTest::construct() {
     constexpr Array<3, Int> a = {5, 6, 7};
     CORRADE_COMPARE(a, (Array<3, Int>(5, 6, 7)));
 
-    #ifndef CORRADE_MSVC2015_COMPATIBILITY
+    constexpr Array<3, Int> a2 = 5;
-    /* Can't use delegating constructors with constexpr -- https://connect.microsoft.com/VisualStudio/feedback/details/1579279/c-constexpr-does-not-work-with-delegating-constructors */
-    constexpr
-    #endif
-    Array<3, Int> a2 = 5;
     CORRADE_COMPARE(a2, (Array<3, Int>(5, 5, 5)));
 
     constexpr Array1D b = 5;