Disallow default construction of tag types.

Caused ambiguous overload problems when using {} in function calls. The tags
should be always specified explicitly.

src/Magnum/Math/Matrix.h

@@ -65,7 +65,7 @@ template<std::size_t size, class T> class Matrix: public RectangularMatrix<size,
         enum ZeroType { Zero };
         #else
         CORRADE_DEPRECATED("use Math::ZeroInitT instead") typedef ZeroInitT ZeroType;
-        CORRADE_DEPRECATED("use Math::ZeroInit instead") constexpr static ZeroInitT Zero{};
+        CORRADE_DEPRECATED("use Math::ZeroInit instead") constexpr static ZeroInitT Zero{ZeroInitT::Init{}};
         #endif
 
         /**
@@ -76,7 +76,7 @@ template<std::size_t size, class T> class Matrix: public RectangularMatrix<size,
         enum IdentityType { Identity };
         #else
         CORRADE_DEPRECATED("use Math::IdentityInitT instead") typedef IdentityInitT IdentityType;
-        CORRADE_DEPRECATED("use Math::IdentityInit instead") constexpr static IdentityInitT Identity{};
+        CORRADE_DEPRECATED("use Math::IdentityInit instead") constexpr static IdentityInitT Identity{IdentityInitT::Init{}};
         #endif
         #endif
         #endif

src/Magnum/Math/RectangularMatrix.h

@@ -400,7 +400,7 @@ template<std::size_t cols, std::size_t rows, class T> class RectangularMatrix {
 
         /* Implementation for RectangularMatrix<cols, rows, T>::RectangularMatrix(ZeroInitT) and RectangularMatrix<cols, rows, T>::RectangularMatrix(NoInitT) */
         /* MSVC 2015 can't handle {} here */
-        template<class U, std::size_t ...sequence> constexpr explicit RectangularMatrix(Implementation::Sequence<sequence...>, U): _data{Vector<rows, T>((static_cast<void>(sequence), U{}))...} {}
+        template<class U, std::size_t ...sequence> constexpr explicit RectangularMatrix(Implementation::Sequence<sequence...>, U): _data{Vector<rows, T>((static_cast<void>(sequence), U{typename U::Init{}}))...} {}
 
         template<std::size_t ...sequence> constexpr Vector<DiagonalSize, T> diagonalInternal(Implementation::Sequence<sequence...>) const;
 

src/Magnum/Math/Tags.h

@@ -47,7 +47,13 @@ typedef Corrade::Containers::NoInitT NoInitT;
 Used to distinguish construction with all elements set to zero.
 @see @ref ZeroInit
 */
-struct ZeroInitT {};
+/* Explicit constructor to avoid ambiguous calls when using {} */
+struct ZeroInitT {
+    #ifndef DOXYGEN_GENERATING_OUTPUT
+    struct Init{};
+    constexpr explicit ZeroInitT(Init) {}
+    #endif
+};
 
 /**
 @brief Identity initialization tag type
@@ -55,7 +61,13 @@ struct ZeroInitT {};
 Used to distinguish construction with transformation set to identity.
 @see @ref IdentityInit
 */
-struct IdentityInitT {};
+/* Explicit constructor to avoid ambiguous calls when using {} */
+struct IdentityInitT {
+    #ifndef DOXYGEN_GENERATING_OUTPUT
+    struct Init{};
+    constexpr explicit IdentityInitT(Init) {}
+    #endif
+};
 
 /**
 @brief No initialization tag
@@ -63,6 +75,7 @@ struct IdentityInitT {};
 Use for construction with no initialization at all.
 */
 #ifdef DOXYGEN_GENERATING_OUTPUT
+/* Explicit constructor to avoid ambiguous calls when using {} */
 constexpr NoInitT NoInit{};
 #else
 using Corrade::Containers::NoInit;
@@ -73,14 +86,14 @@ using Corrade::Containers::NoInit;
 
 Use for construction with all elements set to zero.
 */
-constexpr ZeroInitT ZeroInit{};
+constexpr ZeroInitT ZeroInit{ZeroInitT::Init{}};
 
 /**
 @brief Identity initialization tag
 
 Use for construction with transformation set to identity.
 */
-constexpr IdentityInitT IdentityInit{};
+constexpr IdentityInitT IdentityInit{IdentityInitT::Init{}};
 
 }}
 

src/Magnum/Math/Test/CMakeLists.txt

@@ -26,6 +26,7 @@
 corrade_add_test(MathBoolVectorTest BoolVectorTest.cpp)
 corrade_add_test(MathConstantsTest ConstantsTest.cpp)
 corrade_add_test(MathFunctionsTest FunctionsTest.cpp LIBRARIES MagnumMathTestLib)
+corrade_add_test(MathTagsTest TagsTest.cpp)
 corrade_add_test(MathTypeTraitsTest TypeTraitsTest.cpp)
 
 corrade_add_test(MathVectorTest VectorTest.cpp LIBRARIES MagnumMathTestLib)

src/Magnum/Math/Test/TagsTest.cpp

@@ -0,0 +1,49 @@
+/*
+    This file is part of Magnum.
+
+    Copyright © 2010, 2011, 2012, 2013, 2014, 2015
+              Vladimír Vondruš <mosra@centrum.cz>
+
+    Permission is hereby granted, free of charge, to any person obtaining a
+    copy of this software and associated documentation files (the "Software"),
+    to deal in the Software without restriction, including without limitation
+    the rights to use, copy, modify, merge, publish, distribute, sublicense,
+    and/or sell copies of the Software, and to permit persons to whom the
+    Software is furnished to do so, subject to the following conditions:
+
+    The above copyright notice and this permission notice shall be included
+    in all copies or substantial portions of the Software.
+
+    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+    IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+    THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+    LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+    FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+    DEALINGS IN THE SOFTWARE.
+*/
+
+#include "Magnum/Math/Tags.h"
+#include "Corrade/TestSuite/Tester.h"
+
+namespace Magnum { namespace Math { namespace Test {
+
+struct TagsTest: Corrade::TestSuite::Tester {
+    explicit TagsTest();
+
+    void noDefaultConstructor();
+};
+
+TagsTest::TagsTest() {
+    addTests({&TagsTest::noDefaultConstructor});
+}
+
+void TagsTest::noDefaultConstructor() {
+    CORRADE_VERIFY(!std::is_default_constructible<NoInitT>::value);
+    CORRADE_VERIFY(!std::is_default_constructible<ZeroInitT>::value);
+    CORRADE_VERIFY(!std::is_default_constructible<IdentityInitT>::value);
+}
+
+}}}
+
+CORRADE_TEST_MAIN(Magnum::Math::Test::TagsTest)

src/Magnum/Tags.h

@@ -37,14 +37,20 @@ namespace Magnum {
 Used to distinguish construction without creating the underlying OpenGL object.
 @see @ref NoCreate
 */
-struct NoCreateT {};
+/* Explicit constructor to avoid ambiguous calls when using {} */
+struct NoCreateT {
+    #ifndef DOXYGEN_GENERATING_OUTPUT
+    struct Init{};
+    constexpr explicit NoCreateT(Init) {}
+    #endif
+};
 
 /**
 @brief No creation tag
 
 Use for construction without creating the underlying OpenGL object.
 */
-constexpr NoCreateT NoCreate{};
+constexpr NoCreateT NoCreate{NoCreateT::Init{}};
 
 }
 

src/Magnum/Test/CMakeLists.txt

@@ -39,6 +39,7 @@ corrade_add_test(ResourceManagerTest ResourceManagerTest.cpp LIBRARIES Magnum)
 corrade_add_test(SamplerTest SamplerTest.cpp LIBRARIES Magnum)
 corrade_add_test(ShaderTest ShaderTest.cpp LIBRARIES Magnum)
 corrade_add_test(VersionTest VersionTest.cpp LIBRARIES Magnum)
+corrade_add_test(TagsTest TagsTest.cpp)
 
 add_library(ResourceManagerLocalInstanceTestLib ${SHARED_OR_STATIC} ResourceManagerLocalInstanceTestLib.cpp)
 target_link_libraries(ResourceManagerLocalInstanceTestLib Magnum)

src/Magnum/Test/TagsTest.cpp

@@ -0,0 +1,48 @@
+/*
+    This file is part of Magnum.
+
+    Copyright © 2010, 2011, 2012, 2013, 2014, 2015
+              Vladimír Vondruš <mosra@centrum.cz>
+
+    Permission is hereby granted, free of charge, to any person obtaining a
+    copy of this software and associated documentation files (the "Software"),
+    to deal in the Software without restriction, including without limitation
+    the rights to use, copy, modify, merge, publish, distribute, sublicense,
+    and/or sell copies of the Software, and to permit persons to whom the
+    Software is furnished to do so, subject to the following conditions:
+
+    The above copyright notice and this permission notice shall be included
+    in all copies or substantial portions of the Software.
+
+    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+    IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+    THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+    LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+    FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+    DEALINGS IN THE SOFTWARE.
+*/
+
+#include "Magnum/Tags.h"
+#include "Magnum/Magnum.h"
+#include "Corrade/TestSuite/Tester.h"
+
+namespace Magnum { namespace Test {
+
+struct TagsTest: TestSuite::Tester {
+    explicit TagsTest();
+
+    void noDefaultConstructor();
+};
+
+TagsTest::TagsTest() {
+    addTests({&TagsTest::noDefaultConstructor});
+}
+
+void TagsTest::noDefaultConstructor() {
+    CORRADE_VERIFY(!std::is_default_constructible<NoCreateT>::value);
+}
+
+}}
+
+CORRADE_TEST_MAIN(Magnum::Test::TagsTest)