Hi, everyone!

I'm having trouble with a linker error (I'm using Visual Studio 2008) and I would like to have some tips on solving this problem:

This is my code:


#include "Bill.h"
#include "../Exceptions/InvalidArgumentException.h"



Bill::Bill(string shopName)
	if (shopName == "")
		throw(InvalidArgumentException("The shop name cannot be empty."));

	m_shopName = shopName;



#include <exception>

using namespace std;

class InvalidArgumentException : public exception
	InvalidArgumentException(const char* invalidArgument);

	const char* what() const throw();

	static size_t MaximumMessageLength()
		return 100;

	InvalidArgumentException(const InvalidArgumentException&);

	void InitializeMessage();
	void ValidateArgument(const char* invalidArgument);

	const char* m_invalidArgument;
	char m_message[100];		//TODO: Change the way of returning a const char*. That's ugly to use an automatic-allocated array.



#include <string>

#include "InvalidArgumentException.h"

//Public Methods

InvalidArgumentException::InvalidArgumentException(const char* invalidArgument)

	m_invalidArgument = invalidArgument;

const char* InvalidArgumentException::what() const throw()
	return m_message;

//Private Methods

void InvalidArgumentException::InitializeMessage()
	strcpy_s(m_message, m_invalidArgument);

void InvalidArgumentException::ValidateArgument(const char* invalidArgument)
	if (invalidArgument == 0)
		throw(std::exception("The message pointer is null."));
	else if (strlen(invalidArgument) == 0)
		throw(std::exception("The message is empty."));
	else if (strlen(invalidArgument) > MaximumMessageLength())
		throw(std::exception("The message is too long."));

The linker output is:

1>LINK : .\Output\Debug\Billzilla.exe not found or not built by the last incremental link; performing full link
1>Bill.obj : error LNK2001: unresolved external symbol "private: __thiscall InvalidArgumentException::InvalidArgumentException(class InvalidArgumentException const &)" (??0InvalidArgumentException@@AAE@ABV0@@Z)
1>.\Output\Debug\Billzilla.exe : fatal error LNK1120: 1 unresolved externals

Looks like Bill.obj can't find the constructor symbol in InvalidArgumentException.obj. It's the constructor call in the throw() of Bill.cpp that causes the error. It's been a long time using C++, and I'm unable to solve this problem. Can you help me?

InvalidArgumentException::InvalidArgumentException(class InvalidArgumentException const &)" (??0InvalidArgumentException@@AAE@ABV0@@Z)

I think the problem is that your copy ctor is declared but not defined and somewhere you are trying to make a copy of your class 'InvalidArgumentException' .

InvalidArgumentException(const InvalidArgumentException&);

so you could either provide a copy ctor definition or remove any copy attempts from your code or remove this declaration from your code so that the compiler generates it for you when needed

Thanks for the help! I didn't know that the copy constructor of a class that is thrown needs to be public.