甚至未被引用的类方法的未解析外部符号

Question

我正在创建一个简单的调试线程名称数据库（因为您不能在 windows 中为线程命名，您只能将该名称发送给调试器）。我有这个头文件：

`threadname.h`

class ThreadNameMap {
public:
    void setThreadName( uint32_t id, const std::string &name );

    std::string getThreadName( const uint32_t id ) const;
    // If ID given as string
    std::string getThreadName( const std::string id ) const;
    // If no ID given, current ID is used
    std::string getThreadName( ) const;

    // A singleton getter
    static ThreadNameMap* ThreadNameMap::getInstance();
    // Static getters that use the singleton
    static std::string getName( const uint32_t id );
    static std::string getName( const std::string id );
    static std::string getName( );
private:
    ThreadNameMap() {maxNameLength = 16;};
    int maxNameLength;
    // Map of ids and names
    std::map<uint32_t, std::string> names;
};

这是实现：

`threadname.cpp`

ThreadNameMap* ThreadNameMap::getInstance() {
    static ThreadNameMap inst = ThreadNameMap();
    return &inst;
}

std::string ThreadNameMap::getName( const uint32_t id ) { return getInstance()->getThreadName(id); }
std::string ThreadNameMap::getName( const std::string id ) { return getInstance()->getThreadName(id); }
std::string ThreadNameMap::getName( ) { return getInstance()->getThreadName(); }

void ThreadNameMap::setThreadName( uint32_t id, const std::string &name ) {
    setThreadName_private(id, name.c_str());
    if(id==-1)
        id = boostThreadId();
    names[id] = name;
}

std::string ThreadNameMap::getThreadName( const uint32_t id ) const {
    if( names.count( id )>0)
        return names.at(id);
    else
        return "";
}
std::string ThreadNameMap::getThreadName( const std::string id ) const {
    uint32_t threadNumber = 0;
    sscanf(id.c_str(), "%lx", &threadNumber);
    return getThreadName(threadNumber);
}
/** THIS ONE IS REPORTED AS UNREFERENCED!!! **/
std::string ThreadNameMap::getThreadName( ) const {
    return getThreadName(boostThreadId());
}

我使用单例接口并在我的记录器头文件中像这样访问它：

`logger.h`

#include "... path .../setthreadname.h"
#define LOGMTDBG_tmp(debuglevel, logstream) LOGMT(debugLevel(debuglevel) << datetimeEx << ' ' << ThreadNameMap::getName() << ' ' << __FUNCTION__ << ' ' << logstream)

Logger 包含在许多其他 cpp 和 h 文件中 - 任何需要的地方。其中一些报告未引用的符号：

Error   13  error LNK2001: unresolved external symbol "public: class std::basic_string,class std::allocator > __cdecl ThreadNameMap::getThreadName(void)" (?getThreadName@ThreadNameMap@@QEAA?AV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@XZ)   D:\techsys\RomeoTT\Source\RunWindow.obj
Error   14  error LNK2019: unresolved external symbol "public: class std::basic_string,class std::allocator > __cdecl ThreadNameMap::getThreadName(void)" (?getThreadName@ThreadNameMap@@QEAA?AV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@XZ) referenced in function "private: void __cdecl BaseRunPresenter::MessageHandler(class boost::shared_ptr)" (?MessageHandler@BaseRunPresenter@@AEAAXV?$shared_ptr@USMSSBase@@@boost@@@Z)    D:\techsys\RomeoTT\Source\BaseRunPresenter.obj
Error   15  error LNK2001: unresolved external symbol "public: class std::basic_string,class std::allocator > __cdecl ThreadNameMap::getThreadName(void)" (?getThreadName@ThreadNameMap@@QEAA?AV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@XZ)   D:\techsys\RomeoTT\Source\BaseRunView.obj
Error   16  error LNK2001: unresolved external symbol "public: class std::basic_string,class std::allocator > __cdecl ThreadNameMap::getThreadName(void)" (?getThreadName@ThreadNameMap@@QEAA?AV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@XZ)   D:\techsys\RomeoTT\Source\XmlSestavaRunPresenter.obj
Error   17  error LNK2001: unresolved external symbol "public: class std::basic_string,class std::allocator > __cdecl ThreadNameMap::getThreadName(void)" (?getThreadName@ThreadNameMap@@QEAA?AV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@XZ)   D:\techsys\RomeoTT\Source\RunSestavaFrame.obj
Error   18  error LNK2019: unresolved external symbol "class std::basic_string,class std::allocator > __cdecl getThreadName(void)" (?getThreadName@@YA?AV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@XZ) referenced in function "public: void __cdecl SestavaHeader::DataSource::Dump2LOG(void)const " (?Dump2LOG@DataSource@SestavaHeader@@QEBAXXZ)  D:\techsys\RomeoTT\Source\SestavaDataSource.obj

我搜索了项目，但没有任何class非静态方法的单一引用，只有[中的一个=14=].

我查了很多Unreferenced external symbol的问题，但是都是两种可能：

缺少 dll - 好吧，显然我没有为此使用任何 dll
函数已声明但未实现 - 在上面的代码中您可以看到声明和实现，它们匹配

那么为什么链接器会抱怨甚至没有引用的方法？我试图改变 const 并在 .h 文件中移动静态方法，但没有任何帮助。我现在真的很绝望。

编辑： Visual studio 链接器标志：

/OUT:"D:\techsys\RomeoTT\PROJECT\PROJECTd.exe" /INCREMENTAL /NOLOGO /LIBPATH:"..\..\libs\openssl64\lib\VC\static" /LIBPATH:"..\..\libs\boost155\stage\lib64bit" /LIBPATH:"C:\Qt.3.0-64\qtbase\lib" "libeay32MTd.lib" "Graph64d.lib" "HelpLib64d.lib" "version.lib" "qtmaind.lib" "Qt5Cored.lib" "Qt5Guid.lib" "Qt5Multimediad.lib" "Qt5Sqld.lib" "Qt5PrintSupportd.lib" "Qt5Svgd.lib" "Qt5Widgetsd.lib" "Qt5Xmld.lib" "Qt5XmlPatternsd.lib" "kernel32.lib" "user32.lib" "gdi32.lib" "winspool.lib" "comdlg32.lib" "advapi32.lib" "shell32.lib" "ole32.lib" "oleaut32.lib" "uuid.lib" "odbc32.lib" "odbccp32.lib" /MANIFEST /ManifestFile:"D:\techsys\XXXX\obj\x64\XXXX\Debug\XXXXXd.exe.intermediate.manifest" /ALLOWISOLATION /MANIFESTUAC:"level='asInvoker' uiAccess='false'" /DEBUG /PDB:"D:\techsys\XXXXX\XXXXX64\XXXXXd.pdb" /SUBSYSTEM:WINDOWS /OPT:NOREF /PGD:"D:\techsys\XXXX\XXXX64\XXXXXd.pgd" /TLBID:1 /DYNAMICBASE /NXCOMPAT /MACHINE:X64 /ERRORREPORT:NONE

Answer 1

您通过详细检查错误消息（清理易感性）找到可能的罪魁祸首：

Unresolved external symbol "string stringThreadNameMap::getThreadName(void)" referenced in RunWindow.obj
Unresolved external symbol "string stringThreadNameMap::getThreadName(void)" referenced in function "private: void stringBaseRunPresenter::MessageHandler(class boost::shared_ptr)" referenced in BaseRunPresenter.obj
Unresolved external symbol "string stringThreadNameMap::getThreadName(void)" referenced in BaseRunView.obj
Unresolved external symbol "string stringThreadNameMap::getThreadName(void)" referenced in XmlSestavaRunPresenter.obj
Unresolved external symbol "string stringThreadNameMap::getThreadName(void)" referenced in RunSestavaFrame.obj
Unresolved external symbol "string stringThreadNameMap::getThreadName(void)" referenced in function "public: void stringSestavaHeader::DataSource::Dump2LOG(void)const " SestavaDataSource.obj

这些链接器错误说明的是：

一些目标文件（RunWindow.obj、BaseRunPresenter.obj...）包含对 非常量 方法的引用 getThreadName()
这意味着这些目标文件是在声明方法 getThreadName() 时从源文件生成的 非常量

但是，getThreadName() 的声明现在是 const:

std::string getThreadName( ) const;

因此，这些目标文件中的每一个都是根据 getThreadName() 的过时声明编译的，应该重新编译。如果可能，因为可能存在其他（未检测到的）不一致错误，您应该执行完全重建。

甚至未被引用的类方法的未解析外部符号

Unresolved external symbol for classmethod that isn't even referenced

c++

linker-errors

unresolved-external

c++11

`threadname.h`

`threadname.cpp`

`logger.h`