C++ / CLI linker error because of SHAssocEnumHandlers function - visual-c++

To reproduce the issue,
Create a project > VC++ > CLR > Class library, name the project "ClassLibrary2" and use below two files as is.
// ClassLibrary2.h
#pragma once
#include <msclr\marshal.h>
#include <ShObjIdl.h>
using namespace System;
namespace ClassLibrary2 {
public ref class Class1
{
public : void ClassLibrary2::Class1::GetAllOpenWithProgs(String^ ext);
};
}
// ClassLibrary2.cpp
// This is the main DLL file.
#include "stdafx.h"
#include "ClassLibrary2.h"
void ClassLibrary2::Class1::GetAllOpenWithProgs(String^ ext)
{
msclr::interop::marshal_context ^ context = gcnew msclr::interop::marshal_context();
PCWSTR pszStr = context->marshal_as<const wchar_t*>(ext);
IEnumAssocHandlers *pEnumHandlers = NULL;
/* below line is producing problems */
SHAssocEnumHandlers(pszStr, ASSOC_FILTER_RECOMMENDED, &pEnumHandlers);
}
Now, if I build the project, I get following errors :
Error 2 error LNK2028: unresolved token (0A0000A2) "extern "C" long
__cdecl SHAssocEnumHandlers(wchar_t const *,enum ASSOC_FILTER,struct IEnumAssocHandlers * *)"
(?SHAssocEnumHandlers##$$J0YAJPEB_WW4ASSOC_FILTER##PEAPEAUIEnumAssocHandlers###Z)
referenced in function "public: void __clrcall
ClassLibrary2::Class1::GetAllOpenWithProgs(class System::String ^)"
(?GetAllOpenWithProgs#Class1#ClassLibrary2##$$FQE$AAMXPE$AAVString#System###Z) C:\Users\Anjum\Documents\Visual
Studio
2012\Projects\WpfApplication2\ClassLibrary2\ClassLibrary2.obj ClassLibrary2
Error 3 error LNK2019: unresolved external symbol "extern "C" long
__cdecl SHAssocEnumHandlers(wchar_t const *,enum ASSOC_FILTER,struct IEnumAssocHandlers * *)"
(?SHAssocEnumHandlers##$$J0YAJPEB_WW4ASSOC_FILTER##PEAPEAUIEnumAssocHandlers###Z)
referenced in function "public: void __clrcall
ClassLibrary2::Class1::GetAllOpenWithProgs(class System::String ^)"
(?GetAllOpenWithProgs#Class1#ClassLibrary2##$$FQE$AAMXPE$AAVString#System###Z) C:\Users\Anjum\Documents\Visual
Studio
2012\Projects\WpfApplication2\ClassLibrary2\ClassLibrary2.obj ClassLibrary2
How to remove those linker errors ?

Related

error LNK2019: unresolved external symbol/

I'm having a lot of trouble trying to compile an ogre sample found on Github.
I've had several Intellisense errors, compilation & linking errors. Now I'm stuck with 2 linker errors. I know there's a lot of similar questions around here because I've read a lot on the subject but I can't find (or see) the right solution.
error LNK2019: unresolved external symbol "public: __thiscall NFSpace::PlanetMapTile::PlanetMapTile(struct NFSpace::QuadTreeNode *,class Ogre::SharedPtr<class Ogre::Texture>,class Ogre::Image,class Ogre::SharedPtr<class Ogre::Texture>,int)" (??0PlanetMapTile#NFSpace##QAE#PAUQuadTreeNode#1#V?$SharedPtr#VTexture#Ogre###Ogre##VImage#4#1H#Z) referenced in function "public: class NFSpace::PlanetMapTile * __thiscall NFSpace::PlanetMap::finalizeTile(struct NFSpace::QuadTreeNode *)" (?finalizeTile#PlanetMap#NFSpace##QAEPAVPlanetMapTile#2#PAUQuadTreeNode#2##Z)
error LNK2019: unresolved external symbol "public: struct NFSpace::QuadTreeNode const * __thiscall NFSpace::PlanetMapTile::getNode(void)" (?getNode#PlanetMapTile#NFSpace##QAEPBUQuadTreeNode#2#XZ) referenced in function "public: void __thiscall NFSpace::PlanetRenderable::setFrameOfReference(struct NFSpace::PlanetLODConfiguration &)" (?setFrameOfReference#PlanetRenderable#NFSpace##QAEXAAUPlanetLODConfiguration#2##Z)
here is the code associated with the first error:
PlanetMapTile.h
namespace NFSpace {
class PlanetMapTile {
public:
PlanetMapTile(QuadTreeNode* node, TexturePtr heightTexture, Image heightImage, TexturePtr normalTexture, int size);
~PlanetMapTile();
};
}
PlanetMapTile.cpp
#include "PlanetMapTile.h"
namespace NFSpace {
PlanetMapTile::PlanetMapTile(QuadTreeNode* node, TexturePtr heightTexture, Image heightImage, TexturePtr normalTexture, int size) {
//do something
}
PlanetMapTile::~PlanetMapTile() {
//do something
}
}
PlanetMap.h
#include "PlanetMapTile.h"
namespace NFSpace {
class PlanetMap {
public:
PlanetMapTile* finalizeTile(QuadTreeNode* node);
};
}
PlanetMap.cpp
#include "PlanetMap.h"
namespace NFSpace {
PlanetMapTile* PlanetMap::finalizeTile(QuadTreeNode* node) {
mStep = 0;
return new PlanetMapTile(node, mHeightTexture, mHeightImage, mNormalTexture, getInt("planet.textureSize"));
}
}
Any help would be appreciated.
That is how you should declare the name space
PlanetMApTile.h
namespace NFSpace{
class PlanetMapTile {
public:
PlanetMapTile(QuadTreeNode* node, TexturePtr heightTexture, Image heightImage, TexturePtr normalTexture, int size);
~PlanetMapTile();
};
}
PlanetMapTile.cpp
#include "PlanetMapTile.h"
NFSpace::PlanetMapTile::PlanetMapTile(QuadTreeNode* node, TexturePtr heightTexture, Image heightImage, TexturePtr normalTexture, int size) {
//do something
}
NFSpace::PlanetMapTile::~PlanetMapTile() {
//do something
}
PlanetMap.h
#include "PlanetMapTile.h"
class PlanetMap {
public:
NFSpace::PlanetMapTile* finalizeTile(QuadTreeNode* node);
}
PlanetMap.cpp
#include "PlanetMap.h"
NFSpace::PlanetMapTile* PlanetMap::finalizeTile(QuadTreeNode* node) {
mStep = 0;
return new NFSpace::PlanetMapTile(node, mHeightTexture, mHeightImage, mNormalTexture, getInt("planet.textureSize"));
}
So I've finally found the solution:
Considering the fact that PlanetMapTile() and getNode() were both involving QuadTreeNode* and that ~PlanetMapTile() didn't raise an error, I've started to look at the QuadTreeNode declaration which is located in PlanetCubeTree.h. Then I've just tried to add #include "PlanetCubeTree.h" to PlanetMapTile.h and it solved the error.
Thank you for your help

Unresolved externals in Visual C++

I'm trying to compile a solution in MS Visual Studio C++ 2012.
My code uses marshallsoft AES library.
I added these for library and include paths:
C:\aes4c\APPS to Configuration properties->VC++ Directories->Include Directories
C:\aes4c\DLLS to Configuration properties->VC++ Directories->Library Directories
When I compile the individual .cpp file it compiles without problem but when I build the solution I get:
------ Build started: Project: cryptest2, Configuration: Debug Win32 ------
cryptest2.obj : error LNK2019: unresolved external symbol __imp__aesAttach#8 referenced in function "int __cdecl EncryptFileW(char *,char *)" (?EncryptFileW##YAHPAD0#Z)
cryptest2.obj : error LNK2019: unresolved external symbol __imp__aesEncryptFile#12 referenced in function "int __cdecl EncryptFileW(char *,char *)" (?EncryptFileW##YAHPAD0#Z)
cryptest2.obj : error LNK2019: unresolved external symbol __imp__aesInitAES#20 referenced in function "int __cdecl EncryptFileW(char *,char *)" (?EncryptFileW##YAHPAD0#Z)
C:\Users\ariyan\documents\visual studio 2012\Projects\cryptest2\Debug\cryptest2.exe : fatal error LNK1120: 3 unresolved externals
========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========
What is the problem?
How Can I fix it?
My code is:
#include "stdafx.h"
#include <windows.h>
#include <stdio.h>
#include "aes.h"
int EncryptFile(char *KeyBuffer, char *FileName);
int _tmain(int argc, _TCHAR* argv[])
{
EncryptFile("1234567890abcdef","c:\test.txt");
return 0;
}
int EncryptFile(char *KeyBuffer, char *FileName)
{int Code;
// attach DLL
Code = aesAttach(0, 0);
if(Code<0)
{printf("ERROR %d: Cannot attach\n", Code);
return FALSE;
}
printf("Will encrypt file in CBC mode\n");
Code = aesInitAES((char *)KeyBuffer, NULL, AES_ECB_MODE, AES_ENCRYPT, NULL);
if(Code<0)
{printf("aesInitAES fails\n");
return FALSE;
}
printf("Encrypt file...\n");
Code = aesEncryptFile(NULL, KeyBuffer, FileName);
if(Code<0)
{printf("aesEncryptFile fails\n");
return FALSE;
}
printf("%d bytes encrypted\n", Code);
return Code;
}
It's not enough to add to library path - that just tells the linker where to look for a library if and when it decides to link with it. But you have to tell the linker to look for it in the first place. For that, mention the LIB file name in
Project > Properties > Linker > Input > Additional Dependencies

googletest integrated in CLR/CLI Compilation error LNK2028

Im totally new to google testing in CLI. Just managed to set up and integrate google test with visual studio 2012. However, when I try to include the header file of my project with my tester.h file (because I want to test the functions in that headerfile), I encountered the following error:
Error 2 error LNK2028: unresolved token (0A0006FB) "public: __thiscall ExpenseTracker::ExpenseTracker(void)" (??0ExpenseTracker##$$FQAE#XZ) referenced in function "private: virtual void __thiscall enter_settings_user_login_Test::TestBody(void)" (?TestBody#enter_settings_user_login_Test##$$FEAEXXZ) C:\Users\Jacky\Desktop\EzXpns3\test_project\main.obj test_project
Error 3 error LNK2019: unresolved external symbol "public: __thiscall ExpenseTracker::ExpenseTracker(void)" (??0ExpenseTracker##$$FQAE#XZ) referenced in function "private: virtual void __thiscall enter_settings_user_login_Test::TestBody(void)" (?TestBody#enter_settings_user_login_Test##$$FEAEXXZ) C:\Users\Jia Wei\Desktop\EzXpns3\test_project\main.obj test_project
I have tried including dependencies gtestd.lib, kernel32.lib, user32.lib, advapi32.lib, Ws2_32.lib
Problem slightly resolved. Instead of having expenseTracker.h and ExpenseTracker.cpp, I placed all my implementation of ExpenseTracker.h in the header file itself and everything compiled nicely and test run. However, my entire project has been built on both header file and cpp file and its not very wise to redo everything for testing purposes right? Could anyone help with this?
Attached below are my header files.
//tester.h
#include "gtest/gtest.h" //include to use Google Unit test's stuff
#include "C:\Users\Jacky\Desktop\EzXpns3\Source - testing\EzXpns2\ExpenseTracker.h"
using namespace std;
class ExpenseTracker;
/************************************************************************/
/* We write test cases here */
/************************************************************************/
TEST(basic_test, add_simple_route)
{
ASSERT_EQ(1, 1);
}
TEST(enter_settings, user_login)
{
ExpenseTracker :: ExpenseTracker();
//loadUserInfo();
string username = "XXX_XXX";
string password = "12345";
//myTracker -> loadUserInfo();
//bool result = myTracker -> login(username, password);
//ASSERT_EQ(true, result);
}
void runTest(int argument_count, char** argument_vars)
{
testing::InitGoogleTest(&argument_count, argument_vars); //initialize GTest
RUN_ALL_TESTS();
std::getchar(); //pause the program after all the testing
}
//main.cpp
#include "tester.h"
#include <cstdio>
using namespace System;
using namespace testing;
int main(int argument_count, char** argument_vars)
{
//int argc;
//char** argv;
//runTest(argc, argv);
//InitGoogleTest(argc, argv);
testing::InitGoogleTest(&argument_count, argument_vars); //initialize GTest
RUN_ALL_TESTS();
std::getchar();
return 0;
}
//ExpenseTracker.h, the file which I want to include
#ifndef _EXPENSETRACKER_H
#define _EXPENSETRACKER_H
#include <string>
#include <vector>
#include "user2.h"
using namespace std;
class ExpenseTracker
{
private:
vector<User*> allMyUsers;
public:
ExpenseTracker(); //empty constructor
void addUser(User*);
int findUser(string);
bool login(string, string);
void loadUserInfo();
User* getUser(string);
int getUserSize();
};
#endif;
You need to provide an implementation for the constructor. In other words, you should change:
ExpenseTracker(); //empty constructor
into:
ExpenseTracker() {} // empty constructor
However, since the constructor is empty you might as well remove it entirely!

Matlab / Microsoft Visual C++ 2010 Express: What is "error LNK2019: unresolved external symbol"?

I am trying to create a simple C++ class and a Matlab mex file. My code is as follows:
Matlab: mexTest1.cpp
#include "mex.h"
#include "K:\\My Documents\\Visual Studio 2010\\Projects\\HelloWorld\\HelloWorld\\Class1.h"
/* Input Arguments */
#define X prhs[0]
/* Output Arguments */
#define RESULT plhs[0]
void mexFunction( int nlhs, mxArray *plhs[],
int nrhs, const mxArray *prhs[] ){
/* Initialize input and output pointers
// Inputs */
double *x;
/* Outputs */
double r;
double *result;
mwSize m,n;
m = mxGetM(X);
n = mxGetN(X);
/* Create a matrix for the return argument */
RESULT = mxCreateDoubleMatrix(1, 1, mxREAL);
/* Assign pointers to the various parameters */
result = mxGetPr(RESULT);
x = mxGetPr(X);
/* Do the actual computations in a subroutine */
Class1 c1(2, 15.0);
r = c1.product();
result[0] = r;
return;
}
Class1.h:
#pragma once
#include <string> // Standard string class in C++
class Class1
{
public:
int a;
double b;
public:
Class1(const int& a, const double& b);
//virtual ~Class1();
void print() const;
double product() const;
};
Class1.cpp:
#include "stdafx.h"
#include <iostream>
#include "Class1.h"
Class1::Class1(const int& a, const double& b){
Class1::a = a;
Class1::b = b;
}
void Class1::print() const{
std::cout << "a=" << Class1::a << " * b=" << Class1::b << " = " << Class1::product() << std::endl;
}
double Class1::product() const{
return a*b;
}
Running the Matlab command mex mexTest1.cpp gives the error messages:
Creating library C:\DOCUME~1\K\LOCALS~1\TEMP\MEX_RH~1\templib.x and object C:\DOCUME~1\K\LOCALS~1\TEMP\MEX_RH~1\templib.exp
mexTest1.obj : error LNK2019: unresolved external symbol "public: double __thiscall Class1::product(void)const " (?product#Class1##QBENXZ) referenced in function _mexFunction
mexTest1.obj : error LNK2019: unresolved external symbol "public: __thiscall Class1::Class1(int const &,double const &)" (??0Class1##QAE#ABHABN#Z) referenced in function _mexFunction
mexTest1.mexw32 : fatal error LNK1120: 2 unresolved externals
C:\PROGRA~1\MATLAB\R2011A\BIN\MEX.PL: Error: Link of 'mexTest1.mexw32' failed.
??? Error using ==> mex at 208
Unable to complete successfully.
Can anyone help me fix this problem?
Thanks.
The linker is telling you that in trying to construct an executable, it wasn't supplied with an object file that contains Class1::product and Class1::Class1. That's because those functions would be supplied by compiling Class1.cpp, which your command line doesn't ask for.
You should use the syntax of mex for multiple files: mex mexTest1.cpp Class1.cpp
Your linker is unable to find deinitions(bodies) Class1 methods (constructor and product). This may be due to
You haven't provided any definition(body)
The definitions are in a lib file which you forgot to link to

Singleton code linker errors in vc 9.0. Runs fine in linux compiled with gcc

I have a simple logger that is implemented as a singleton. It works like i want when I compile and run it with g++ in linux but when I compile in Visual Studio 9.0 with vc++ I get the following errors. Is there a way to fix this? I don't mind changing the logger class around, but I would like to avoid changing how it is called.
1>Linking...
1>loggerTest.obj : error LNK2005: "public: static class Logger * __cdecl Logger::getInstance(void)" (?getInstance#Logger##SAPAV1#XZ) already defined in Logger.obj
1>loggerTest.obj : error LNK2005: "public: void __thiscall Logger::log(class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &)" (?log#Logger##QAEXABV?$basic_string#DU?$char_traits#D#std##V?$allocator#D#2##std###Z) already defined in Logger.obj
1>loggerTest.obj : error LNK2005: "public: void __thiscall Logger::closeLog(void)" (?closeLog#Logger##QAEXXZ) already defined in Logger.obj
1>loggerTest.obj : error LNK2005: "private: static class Logger * Logger::_instance" (?_instance#Logger##0PAV1#A) already defined in Logger.obj
1>Logger.obj : error LNK2001: unresolved external symbol "private: static class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > Logger::_path" (?_path#Logger##0V?$basic_string#DU?$char_traits#D#std##V?$allocator#D#2##std##A)
1>loggerTest.obj : error LNK2001: unresolved external symbol "private: static class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > Logger::_path" (?_path#Logger##0V?$basic_string#DU?$char_traits#D#std##V?$allocator#D#2##std##A)
1>Logger.obj : error LNK2001: unresolved external symbol "private: static class boost::mutex Logger::_mutex" (?_mutex#Logger##0Vmutex#boost##A)
1>loggerTest.obj : error LNK2001: unresolved external symbol "private: static class boost::mutex Logger::_mutex" (?_mutex#Logger##0Vmutex#boost##A)
1>Logger.obj : error LNK2001: unresolved external symbol "private: static class std::basic_ofstream<char,struct std::char_traits<char> > Logger::_log" (?_log#Logger##0V?$basic_ofstream#DU?$char_traits#D#std###std##A)
1>loggerTest.obj : error LNK2001: unresolved external symbol "private: static class std::basic_ofstream<char,struct std::char_traits<char> > Logger::_log" (?_log#Logger##0V?$basic_ofstream#DU?$char_traits#D#std###std##A)
The code, three files Logger.h Logger.cpp test.cpp
#ifndef __LOGGER_CPP__
#define __LOGGER_CPP__
#include "Logger.h"
Logger* Logger::_instance = 0;
//string Logger::_path = "log";
//ofstream Logger::_log;
//boost::mutex Logger::_mutex;
Logger* Logger::getInstance(){
{
boost::mutex::scoped_lock lock(_mutex);
if(_instance == 0) {
_instance = new Logger;
_path = "log";
}
} //mutex
return _instance;
}
void Logger::log(const std::string& msg){
{
boost::mutex::scoped_lock lock(_mutex);
if(!_log.is_open()){
_log.open(_path.c_str());
}
if(_log.is_open()){
_log << msg.c_str() << std::endl;
}
}
}
void Logger::closeLog(){
Logger::_log.close();
}
#endif
` ...
#ifndef __LOGGER_H__
#define __LOGGER_H__
#include <iostream>
#include <string>
#include <fstream>
#include <boost/thread/mutex.hpp>
#include <boost/thread.hpp>
using namespace std;
class Logger {
public:
static Logger* getInstance();
void log(const std::string& msg);
void closeLog();
protected:
Logger(){}
private:
static Logger* _instance;
static string _path;
static bool _logOpen;
static ofstream _log;
static boost::mutex _mutex; //check mutable
};
#endif
test.cpp
`
#include <iostream>
#include "Logger.cpp"
using namespace std;
int main(int argc, char *argv[])
{
Logger* log = Logger::getInstance();
log->log("hello world\n");
return 0;
}
This is a problem because you've defined the symbol multiple times by compiling the CPP then also including it in test.cpp... By convention you should only include the declaration, not the definition as you've done.
I am surprised that gcc would allow one to be so lax about this.
change
#include "Logger.cpp"
to
#include "Logger.h"
and give it a try.
The problem is because you have done #include "Logger.cpp" instead of #include "Logger.h" in test.cpp . Because of this, the symbols inside the Logger.cpp will be defined multiple times (once for the translation unit logger.cpp and once for test.cpp). Having multiple inclusion guard doesn't help because it works only within a translation unit.

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