Implementation of C++14's make_unique for C++11 compilers.

src/libs/vdxf/libdxfrw/drw_base.h

@@ -22,10 +22,6 @@
 #include <QtGlobal>
 #include <ciso646>
 
-#if ((defined(_MSVC_LANG) && _MSVC_LANG < 201402L) || __cplusplus < 201402L)
-#include <memory>
-#endif
-
 #ifdef DRW_ASSERTS
 # define drw_assert(a) assert(a)
 #else
@@ -86,13 +82,6 @@
 #endif // defined(__cplusplus)
 #endif // QT_VERSION < QT_VERSION_CHECK(5, 8, 0)
 
-#if ((defined(_MSVC_LANG) && _MSVC_LANG < 201402L) || __cplusplus < 201402L)
-template<typename T, typename... Args>
-std::unique_ptr<T> make_unique(Args&&... args) {
-    return std::unique_ptr<T>(new T(std::forward<Args>(args)...));
-}
-#endif
-
 typedef signed char dint8;              /* 8 bit signed */
 typedef signed short dint16;            /* 16 bit signed */
 typedef signed int dint32;              /* 32 bit signed */

src/libs/vdxf/libdxfrw/intern/drw_dbg.cpp

@@ -12,7 +12,7 @@
 
 #include <iostream>
 #include <iomanip>
-#include <memory>
+#include "make_unique.h"
 #include "drw_dbg.h"
 
 DRW_dbg *DRW_dbg::instance{nullptr};

src/libs/vdxf/libdxfrw/intern/make_unique.h

@@ -0,0 +1,141 @@
+// Implementation of C++14's make_unique for C++11 compilers.
+//
+// This has been tested with:
+// - MSVC 11.0 (Visual Studio 2012)
+// - gcc 4.6.3
+// - Xcode 4.4 (with clang "4.0")
+//
+// It is based off an implementation proposed by Stephan T. Lavavej for
+// inclusion in the C++14 standard:
+//    http://isocpp.org/files/papers/N3656.txt
+// Where appropriate, it borrows the use of MSVC's _VARIADIC_EXPAND_0X macro
+// machinery to compensate for lack of variadic templates.
+//
+// This file injects make_unique into the std namespace, which I acknowledge is
+// technically forbidden ([C++11: 17.6.4.2.2.1/1]), but is necessary in order
+// to have syntax compatibility with C++14.
+//
+// I perform compiler version checking for MSVC, gcc, and clang to ensure that
+// we don't add make_unique if it is already there (instead, we include
+// <memory> to get the compiler-provided one). You can override the compiler
+// version checking by defining the symbol COMPILER_SUPPORTS_MAKE_UNIQUE.
+//
+//
+// ===============================================================================
+// This file is released into the public domain. See LICENCE for more information.
+// ===============================================================================
+
+#pragma once
+
+// If user hasn't specified COMPILER_SUPPORTS_MAKE_UNIQUE then try to figure out
+// based on compiler version if std::make_unique is provided.
+#if !defined(COMPILER_SUPPORTS_MAKE_UNIQUE)
+   #if defined(_MSC_VER)
+      // std::make_unique was added in MSVC 12.0
+      #if _MSC_VER >= 1800 // MSVC 12.0 (Visual Studio 2013)
+         #define COMPILER_SUPPORTS_MAKE_UNIQUE
+      #endif
+   #elif defined(__clang__)
+      // std::make_unique was added in clang 3.4, but not until Xcode 6.
+      // Annoyingly, Apple makes the clang version defines match the version
+      // of Xcode, not the version of clang.
+      #define CLANG_VERSION (__clang_major__ * 10000 + __clang_minor__ * 100 + __clang_patchlevel__)
+      #if defined(__APPLE__) && CLANG_VERSION >= 60000
+         #define COMPILER_SUPPORTS_MAKE_UNIQUE
+      #elif !defined(__APPLE__) && CLANG_VERSION >= 30400 
+         #define COMPILER_SUPPORTS_MAKE_UNIQUE
+      #endif
+   #elif defined(__GNUC__)
+      // std::make_unique was added in gcc 4.9, for standards versions greater
+      // than -std=c++11.
+      #define GCC_VERSION (__GNUC__ * 10000 + __GNUC_MINOR__ * 100 + __GNUC_PATCHLEVEL__)
+      #if GCC_VERSION >= 40900 && __cplusplus > 201103L
+         #define COMPILER_SUPPORTS_MAKE_UNIQUE
+      #endif
+   #endif
+#endif
+
+#if defined(COMPILER_SUPPORTS_MAKE_UNIQUE)
+
+// If the compiler supports std::make_unique, then pull in <memory> to get it.
+#include <memory>
+
+#else
+
+// Otherwise, the compiler doesn't provide it, so implement it ourselves.
+
+#include <cstddef>
+#include <memory>
+#include <type_traits>
+#include <utility>
+
+namespace std {
+
+template<class _Ty> struct _Unique_if {
+   typedef unique_ptr<_Ty> _Single_object;
+};
+
+template<class _Ty> struct _Unique_if<_Ty[]> {
+   typedef unique_ptr<_Ty[]> _Unknown_bound;
+};
+
+template<class _Ty, size_t N> struct _Unique_if<_Ty[N]> {
+   typedef void _Known_bound;
+};
+
+//
+// template< class T, class... Args >
+// unique_ptr<T> make_unique( Args&&... args);
+//
+
+#if defined(_MSC_VER) && (_MSC_VER < 1800)
+
+// Macro machinery because MSVC 11.0 doesn't support variadic templates.
+// The _VARIADIC_EXPAND_0X stuff is defined in <xstddef>
+#define _MAKE_UNIQUE( \
+   TEMPLATE_LIST, PADDING_LIST, LIST, COMMA, X1, X2, X3, X4) \
+   template<class _Ty COMMA LIST(_CLASS_TYPE)> inline \
+      typename _Unique_if<_Ty>::_Single_object make_unique(LIST(_TYPE_REFREF_ARG)) \
+   { \
+      return unique_ptr<_Ty>(new _Ty(LIST(_FORWARD_ARG))); \
+   } \
+
+_VARIADIC_EXPAND_0X(_MAKE_UNIQUE, , , , )
+#undef _MAKE_UNIQUE
+
+#else // not MSVC 11.0 or earlier
+
+template<class _Ty, class... Args>
+   typename _Unique_if<_Ty>::_Single_object
+   make_unique(Args&&... args) {
+      return unique_ptr<_Ty>(new _Ty(std::forward<Args>(args)...));
+   }
+
+#endif
+
+// template< class T >
+// unique_ptr<T> make_unique( std::size_t size );
+
+template<class _Ty>
+   typename _Unique_if<_Ty>::_Unknown_bound
+   make_unique(size_t n) {
+      typedef typename remove_extent<_Ty>::type U;
+      return unique_ptr<_Ty>(new U[n]());
+   }
+
+// template< class T, class... Args >
+// /* unspecified */ make_unique( Args&&... args ) = delete;
+
+// MSVC 11.0 doesn't support deleted functions, so the best we can do
+// is simply not define the function.
+#if !(defined(_MSC_VER) && (_MSC_VER < 1800))
+
+template<class T, class... Args>
+   typename _Unique_if<T>::_Known_bound
+   make_unique(Args&&...) = delete;
+
+#endif
+
+} // namespace std
+
+#endif // !COMPILER_SUPPORTS_MAKE_UNIQUE

src/libs/vdxf/vdxf.pri

@@ -21,6 +21,7 @@ SOURCES += \
 
 HEADERS += \
     $$PWD/libdxfrw/drw_reserve.h \
+    $$PWD/libdxfrw/intern/make_unique.h \
     $$PWD/stable.h \
     $$PWD/vdxfengine.h \
     $$PWD/vdxfpaintdevice.h \