错误：C2061：语法错误：标识符'concurrent_vector <`template-type-parameter-1'，`template-type-parameter-2'>'

问题描述

代码可以在Linux和macOS上正常编译/运行。在Windows 10上，我正在使用Visual Studio 2017工具链编译代码，但是我收到此错误：

...\deps\tbb-2020.3-win\tbb\include\tbb\concurrent_vector.h:680: error: C2061: Syntax error: identifier 'concurrent_vector<'template-type-parameter-1','template-type-parameter-2'>'

此模板concurrent_vector处发生错误：

    //! copying constructor for vector with different allocator type
    template<class M>
    __TBB_DEPRECATED concurrent_vector( const concurrent_vector<T,M>& vector,const allocator_type& a = allocator_type() )
        : internal::allocator_base<T,A>(a),internal::concurrent_vector_base()
    {
        vector_allocator_ptr = &internal_allocator;
        __TBB_TRY {
            internal_copy(vector.internal_vector_base(),sizeof(T),&copy_array);
        } __TBB_CATCH(...) {
            segment_t *table = my_segment.load<relaxed>();
            internal_free_segments( table,internal_clear(&destroy_array),my_first_block.load<relaxed>() );
            __TBB_RETHROW();
        }
    }

该错误发生在TBB标头内：

C:\...\deps\tbb-2020.3-win\tbb\include\tbb\concurrent_vector.h

可能是什么原因？

这是更完整的错误日志：

c:\users\m3\repos\3d-editor\editorlib\deps\tbb-2020.3-win\tbb\include\tbb\concurrent_vector.h(680): error C2061: Syntax error: identifier 'concurrent_vector<`template-type-parameter-1',`template-type-parameter-2'>'
c:\users\m3\repos\3d-editor\editorlib\deps\tbb-2020.3-win\tbb\include\tbb\concurrent_vector.h(1167): note: see reference to class template instantiation 'tbb::concurrent_vector<T,A>' being compiled
C:\Program Files (x86)\Microsoft Visual Studio\2017\Community\VC\Tools\MSVC\14.16.27023\include\memory_resource(860): note: see reference to class template instantiation 'std::pmr::_Intrusive_stack<std::pmr::monotonic_buffer_resource::_Header,void>' being compiled
C:\Program Files (x86)\Microsoft Visual Studio\2017\Community\VC\Tools\MSVC\14.16.27023\include\memory_resource(465): note: see reference to class template instantiation 'std::pmr::_Intrusive_stack<std::pmr::unsynchronized_pool_resource::_Pool::_Chunk,void>' being compiled
c:\users\m3\repos\3d-editor\editorlib\deps\tbb-2020.3-win\tbb\include\tbb\concurrent_vector.h(681): error C2334: unexpected token(s) preceding ':'; skipping apparent function body
c:\users\m3\repos\3d-editor\editorlib\deps\tbb-2020.3-win\tbb\include\tbb\concurrent_vector.h(61): Fatal error C1075: '{': no matching token found
jom: C:\Users\m3\repos\build-3dsceneeditor-Desktop_Qt_5_12_9_MSVC2017_64bit-Debug\editorlib\Makefile.Debug [debug\openvdbutils.obj] Error 2

此代码可与Visual Studio 2017中的/Zc:__cplusplus编译器标志一起用于重新创建问题：

#include <tbb/concurrent_vector.h>
int main()
{
    tbb::concurrent_vector<int> vector;
    vector.push_back(1);
    return 0;
}

解决方法

这似乎是视觉工作室的错误。在TBB github存储库上的issue中，/Zc:__cplusplus编译器标志是原因。

启用该标志会使this code使用c ++ 14 [[deprecated]]属性：

    #if (__cplusplus >= 201402L)
        #define __TBB_DEPRECATED [[deprecated]]
        #define __TBB_DEPRECATED_MSG(msg) [[deprecated(msg)]]
    #elif _MSC_VER
        #define __TBB_DEPRECATED __declspec(deprecated)
        #define __TBB_DEPRECATED_MSG(msg) __declspec(deprecated(msg))
    #elif (__GNUC__ && __TBB_GCC_VERSION >= 40805) || __clang__
        #define __TBB_DEPRECATED __attribute__((deprecated))
        #define __TBB_DEPRECATED_MSG(msg) __attribute__((deprecated(msg)))
    #endif

将此代码交换为始终使用Visual Studio特定的代码似乎可以解决此问题：

    #if _MSC_VER
        #define __TBB_DEPRECATED __declspec(deprecated)
        #define __TBB_DEPRECATED_MSG(msg) __declspec(deprecated(msg))
    #elif (__cplusplus >= 201402L)
        #define __TBB_DEPRECATED [[deprecated]]
        #define __TBB_DEPRECATED_MSG(msg) [[deprecated(msg)]]
    #elif (__GNUC__ && __TBB_GCC_VERSION >= 40805) || __clang__
        #define __TBB_DEPRECATED __attribute__((deprecated))
        #define __TBB_DEPRECATED_MSG(msg) __attribute__((deprecated(msg)))
    #endif

同一个问题的smaller demonstration是：

template <typename T>
class Foo
{
public:
    Foo() {}

    template <typename X>
    [[deprecated]] Foo(const Foo<T>& a)
    {
    }
};

int main()
{
    Foo<int> x;
    return 0;
}

这仅在Visual Studio 2017 it works in 2019中不起作用，因此最简单的解决方法是更新Visual Studio。

已创建一个pull request来解决此问题，reported to Microsoft我不希望MS对其进行修复，因为它已在2019年修复。

,

如here所述，一个简短的解决方法是在Windows上降级为 TBB 2020 Update 1 。感谢@AlanBirtles