我试图在Visual Studio 2015中编译一个我正在制作的DLL，它充当了与OpenVDB的某些功能相关的C兼容包装器，使其可以在现有的C项目中使用。但是，当我构建时，我得到以下链接器错误：
Error LNK2019 unresolved external symbol "__declspec(dllimport) public: class std::shared_ptr<class std::basic_streambuf<char,struct std::char_traits<char> > > __thiscall openvdb::v4_0_1::io::MappedFile::createBuffer(void)const " (__imp_?createBuffer@MappedFile@io@v4_0_1@openvdb@@QBE?AV?$shared_ptr@V?$basic_streambuf@DU?$char_traits@D@std@@@std@@@std@@XZ) referenced in function "private: void __thiscall openvdb::v4_0_1::tree::LeafBuffer<float,3>::doLoad(void)const " (?doLoad@?$LeafBuffer@M$02@tree@v4_0_1@openvdb@@ABEXXZ)
Error LNK2019 unresolved external symbol "__declspec(dllimport) class std::shared_ptr<class openvdb::v4_0_1::io::StreamMetadata> __cdecl openvdb::v4_0_1::io::getStreamMetadataPtr(class std::ios_base &)" (__imp_?getStreamMetadataPtr@io@v4_0_1@openvdb@@YA?AV?$shared_ptr@VStreamMetadata@io@v4_0_1@openvdb@@@std@@AAVios_base@5@@Z) referenced in function "void __cdecl openvdb::v4_0_1::io::readCompressedValues<float,class openvdb::v4_0_1::util::NodeMask<3> >(class std::basic_istream<char,struct std::char_traits<char> > &,float *,unsigned int,class openvdb::v4_0_1::util::NodeMask<3> const &,bool)" (??$readCompressedValues@MV?$NodeMask@$02@util@v4_0_1@openvdb@@@io@v4_0_1@openvdb@@YAXAAV?$basic_istream@DU?$char_traits@D@std@@@std@@PAMIABV?$NodeMask@$02@util@12@_N@Z)
Error LNK2019 unresolved external symbol "__declspec(dllimport) void __cdecl openvdb::v4_0_1::io::setStreamMetadataPtr(class std::ios_base &,class std::shared_ptr<class openvdb::v4_0_1::io::StreamMetadata> &,bool)" (__imp_?setStreamMetadataPtr@io@v4_0_1@openvdb@@YAXAAVios_base@std@@AAV?$shared_ptr@VStreamMetadata@io@v4_0_1@openvdb@@@5@_N@Z) referenced in function "private: void __thiscall openvdb::v4_0_1::tree::LeafBuffer<float,3>::doLoad(void)const " (?doLoad@?$LeafBuffer@M$02@tree@v4_0_1@openvdb@@ABEXXZ)
Error LNK2019 unresolved external symbol "__declspec(dllimport) public: static class std::shared_ptr<class openvdb::v4_0_1::math::Transform> __cdecl openvdb::v4_0_1::math::Transform::createLinearTransform(class openvdb::v4_0_1::math::Mat4<double> const &)" (__imp_?createLinearTransform@Transform@math@v4_0_1@openvdb@@SA?AV?$shared_ptr@VTransform@math@v4_0_1@openvdb@@@std@@ABV?$Mat4@N@234@@Z) referenced in function "public: static class std::shared_ptr<class openvdb::v4_0_1::math::Transform> __cdecl OpenVDB_c::LinearTransform(double,double,double,double,double,double,double,double,double,double,double,double,double,double,double,double)" (?LinearTransform@OpenVDB_c@@SA?AV?$shared_ptr@VTransform@math@v4_0_1@openvdb@@@std@@NNNNNNNNNNNNNNNN@Z)
Error LNK2019 unresolved external symbol "__declspec(dllimport) public: void __thiscall openvdb::v4_0_1::GridBase::setTransform(class std::shared_ptr<class openvdb::v4_0_1::math::Transform>)" (__imp_?setTransform@GridBase@v4_0_1@openvdb@@QAEXV?$shared_ptr@VTransform@math@v4_0_1@openvdb@@@std@@@Z) referenced in function __catch$?setGridTransform@OpenVDB_c@@QAE_NHV?$shared_ptr@VTransform@math@v4_0_1@openvdb@@@std@@@Z$0
Error LNK2019 unresolved external symbol "__declspec(dllimport) public: class std::shared_ptr<class openvdb::v4_0_1::GridBase> __thiscall openvdb::v4_0_1::io::File::readGrid(class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &)" (__imp_?readGrid@File@io@v4_0_1@openvdb@@QAE?AV?$shared_ptr@VGridBase@v4_0_1@openvdb@@@std@@ABV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@6@@Z) referenced in function "public: int __thiscall OpenVDB_c::readGrid(int,char *)" (?readGrid@OpenVDB_c@@QAEHHPAD@Z)
Error LNK2001 unresolved external symbol "public: virtual class std::shared_ptr<class openvdb::v4_0_1::io::Archive> __thiscall openvdb::v4_0_1::io::File::copy(void)const " (?copy@File@io@v4_0_1@openvdb@@UBE?AV?$shared_ptr@VArchive@io@v4_0_1@openvdb@@@std@@XZ)
Error LNK2001 unresolved external symbol "public: virtual void __thiscall openvdb::v4_0_1::io::File::write(class std::vector<class std::shared_ptr<class openvdb::v4_0_1::GridBase const >,class std::allocator<class std::shared_ptr<class openvdb::v4_0_1::GridBase const > > > const &,class openvdb::v4_0_1::MetaMap const &)const " (?write@File@io@v4_0_1@openvdb@@UBEXABV?$vector@V?$shared_ptr@$$CBVGridBase@v4_0_1@openvdb@@@std@@V?$allocator@V?$shared_ptr@$$CBVGridBase@v4_0_1@openvdb@@@std@@@2@@std@@ABVMetaMap@34@@Z)
Error LNK2001 unresolved external symbol "__declspec(dllimport) private: static union half::uif const * const half::_toFloat" (__imp_?_toFloat@half@@0QBTuif@1@B) C:\Users\t00001657\documents\visual studio 2015\Projects\OVDBC\OVDBC\ovdbc.obj 1
OpenVDB及其所有依赖项都在include文件夹中，其目录被添加到其他include目录中，这是我目前Linker选项下的Additional Dependencies列表：
我似乎无法在Visual Studio中找到有关使用OpenVDB进行编译的任何信息来涵盖这种错误，而且我很难忘记我可能会忘记的内容。
结果证明是两个问题的组合：
最后，我需要做的就是定义OPENEXR_DLL，HALF_EXPORTS和OPENVDB_3_ABI_COMPATIBLE，并将构建选项切换为/ MDd。