Visual C++ Woes (Solved)

clsCorwin

Note, right now, I'm not asking for any help with any of my functions UNLESS they are my problem.

Basically running into another Visual Studio problem. Mind you, I am now using Visual Studio 2005 (and not VC++ Express like before).

I compile, and get these:
MSVCRTD.lib(crtexew.obj) : error LNK2019: unresolved external symbol _WinMain@16 referenced in function ___tmainCRTStartup

CTrees.exe : fatal error LNK1120: 1 unresolved externals

I've googled the error and tried what was suggested on the MSDN forums (changing linker properties from console to windows and vice versa, or even setting it to none and manually defining the entry point.) Still get this linker error.

So, anyone got an idea?


Heres my various .cpp and .h files:
Node.h

#pragma once

typedef char STRING[20];

struct NODE
{
	STRING data;
	NODE *left;
	NODE *right;
};

Tree.h

#include "Node.h"
#pragma once

typedef NODE * NODEPTR;

class TREE
{
	NODEPTR root;
	int count;

	void add(NODEPTR & r, STRING str);
	void destroy(NODEPTR r);

//actual traversing functions
	void preorder(NODEPTR r);
	void inorder(NODEPTR r);
	void postorder(NODEPTR r);

public:
//basic ADT functions
	TREE();
	~TREE();
	void create();
	void destroy();
	void add(STRING str);
	void remove(STRING &str);
	bool empty();
	bool full();

//search functions
	int getCount();
	void search(STRING str);

//traversing wrapper functions
	void preorder();
	void inorder();
	void postorder();
};

Tree.cpp

#define _CRT_SECURE_NO_DEPRECATE
#include <string>
#include <iostream>
#include "Tree.h"

using namespace std;

void TREE::add(NODEPTR & r, STRING str)
{
	if( r == 0 )
	{
		NODEPTR temp;
		temp = new NODE;
		strcpy(temp->data, str);
		temp->left = 0;
		temp->right = 0;
		r = temp;
	}
	else if( str < r->data )
		add(r->left, str);
	else
		add(r->right, str);
}

void TREE::destroy(NODEPTR r)
{
	if( r!= 0 )
	{
		destroy(r->left);
		destroy(r->right);
		delete r;
	}
}

void TREE::preorder(NODEPTR r)
{
	if( r != 0 )
	{
		cout << r->data << endl;
		inorder(r->left);
		inorder(r->right);		
	}
}

void TREE::inorder(NODEPTR r)
{
	if(r != 0)
	{
		inorder(r->left);
		cout << r->data << endl;
		inorder(r->right);
	}
}

void TREE::postorder(NODEPTR r)
{
	if(r != 0)
	{
		inorder(r->left);
		inorder(r->right);
		cout << r->data << endl;
	}	
}

TREE::TREE()
{
	TREE::create();
}

TREE::~TREE()
{
	TREE::destroy();
}

void TREE::create()
{
	root = 0;				//initialize the pointer to 0
	count = 0;				//set counter
}

void TREE::destroy()
{
	destroy(root);
}

void TREE::add(STRING str)
{
	add(root, str);
}

void TREE::remove(STRING &str)
{

	count--;
}

bool TREE::empty()
{
	return root == 0;			
}

bool TREE::full()
{
	bool result = false;
	NODEPTR temp;					//create a pointer
	temp = new NODE;			//point temp to a newly create block of RAM
	if( temp == 0 )				//0 = no memory left = full
	{
		result = true;
		delete temp;
	}
	return result;				
}

int TREE::getCount()
{
	return count;
}

void TREE::search(STRING str)
{

}

void TREE::preorder()
{
	preorder(root);
}

void TREE::inorder()
{
	inorder(root);
}

void TREE::postorder()
{
	postorder(root);
}

Philodox

Your program needs an entry point so that the program can start. It doesn't necessarily have to be WinMain (although that is the Windows convention) unless you're writing a Windows gui application. I didn't see a main method in any of your source file listings.

clsCorwin

I have a generic one that pretty much just #inlcudes Tree.h and says int main(){ return 0; } and I still get the error.

ecco the dolphin

Have you included the cpp file that has the main() function into your project?

Also, I believe the main() function is looked at only if you have a console application. For Windows applications, it's WinMain so make sure that your project settings are for a console application.

Philodox

It might be easier to recreate the project specifically as a console application. There is a way to do it through project settings but I've never been able to do it.

clsCorwin

the .cpp file with the main() does #include Tree.h

I ahve set the setting to console already, and I still get this error.

Senjutsu

clsCorwin wrote: »

the .cpp file with the main() does #include Tree.h

...That doesn't mean VC++ knows about the file main is in, or to link it in.

"#include" has nothing to do with linking. All the compiler does when it sees "#include 'Tree.h'" is replace that statement with the text in the file Tree.h. It doesn't do anything about linking object files together. This isn't Java or C#.

Philodox

In a C++ project, any file in the source files section gets compiled. So long as your file with the main() is in the source section it should be picked up.

clsCorwin

Umm, well let me put it this way. For EVERY other multi file project I've done this semester, they've compile just fine without link errors. And the files work together just fine.

ecco the dolphin

Maybe you could post what your Build output is when you do a "Rebuild Solution"?

It looks something like:

1>

---

Rebuild All started: Project: Test, Configuration: Debug Win32

---

1>Deleting intermediate and output files for project 'Test', configuration 'Debug|Win32'
1>Compiling...
1>Source1.cpp
1>Compiling manifest to resources...
1>Linking...
1>Embedding manifest...
1>Build log was saved at "file://e:\Temp\Test\Test\Debug\BuildLog.htm"
1>Test - 0 error(s), 0 warning(s)
========== Rebuild All: 1 succeeded, 0 failed, 0 skipped ==========

Maybe there's something there that'll give a bit more information?

clsCorwin

---

Rebuild All started: Project: Trees, Configuration: Debug Win32

---

Deleting intermediate and output files for project 'Trees', configuration 'Debug|Win32'
Compiling...
Spellcheck.cpp
Tree.cpp
Generating Code...
Compiling manifest to resources...
Linking...
MSVCRTD.lib(crtexew.obj) : error LNK2019: unresolved external symbol _WinMain@16 referenced in function ___tmainCRTStartup
C:\Documents and Settings\Lucas\My Documents\Visual Studio 2005\Projects\Trees\Debug\Trees.exe : fatal error LNK1120: 1 unresolved externals
Build log was saved at "file://c:\Documents and Settings\Lucas\My Documents\Visual Studio 2005\Projects\Trees\Trees\Debug\BuildLog.htm"
Trees - 2 error(s), 0 warning(s)
========== Rebuild All: 0 succeeded, 1 failed, 0 skipped ==========

clsCorwin

And the build log:
Rebuild started: Project: Trees, Configuration: Debug|Win32

Command Lines


Creating temporary file "c:\Documents and Settings\Lucas\My Documents\Visual Studio 2005\Projects\Trees\Trees\Debug\RSP00000339962848.rsp" with contents
[
/Od /D "WIN32" /D "_DEBUG" /D "_CONSOLE" /D "_UNICODE" /D "UNICODE" /Gm /EHsc /RTC1 /MDd /Fo"Debug\\" /Fd"Debug\vc80.pdb" /W3 /c /Wp64 /ZI /TP ".\Tree.cpp"

".\Spellcheck.cpp"
]
Creating command line "cl.exe @c:\Documents and Settings\Lucas\My Documents\Visual Studio 2005\Projects\Trees\Trees\Debug\RSP00000339962848.rsp /nologo /errorReport:prompt"
Creating temporary file "c:\Documents and Settings\Lucas\My Documents\Visual Studio 2005\Projects\Trees\Trees\Debug\TMP00000439962848.tmp" with contents
[
1 /* CREATEPROCESS_MANIFEST_RESOURCE_ID */ 24 /* RT_MANIFEST */ ".\\Debug\\Trees.exe.embed.manifest"
]
Creating command line "rc.exe /fo".\Debug\Trees.exe.embed.manifest.res" "c:\Documents and Settings\Lucas\My Documents\Visual Studio 2005\Projects\Trees\Trees\Debug\TMP00000439962848.tmp""
Creating temporary file "c:\Documents and Settings\Lucas\My Documents\Visual Studio 2005\Projects\Trees\Trees\Debug\RSP00000539962848.rsp" with contents
[
/OUT:"C:\Documents and Settings\Lucas\My Documents\Visual Studio 2005\Projects\Trees\Debug\Trees.exe" /INCREMENTAL /MANIFEST /MANIFESTFILE:"Debug\Trees.exe.intermediate.manifest" /DEBUG /PDB:"c:\Documents and Settings\Lucas\My Documents\Visual Studio 2005\Projects\Trees\debug\Trees.pdb" /SUBSYSTEM:WINDOWS /MACHINE:X86 kernel32.lib user32.lib gdi32.lib winspool.lib comdlg32.lib advapi32.lib shell32.lib ole32.lib oleaut32.lib uuid.lib odbc32.lib odbccp32.lib

".\Debug\Spellcheck.obj"

".\Debug\Tree.obj"

".\Debug\Trees.exe.embed.manifest.res"
]
Creating command line "link.exe @c:\Documents and Settings\Lucas\My Documents\Visual Studio 2005\Projects\Trees\Trees\Debug\RSP00000539962848.rsp /NOLOGO /ERRORREPORT:PROMPT"

Output Window


Compiling...
Spellcheck.cpp
Tree.cpp
Generating Code...
Compiling manifest to resources...
Linking...
MSVCRTD.lib(crtexew.obj) : error LNK2019: unresolved external symbol _WinMain@16 referenced in function ___tmainCRTStartup
C:\Documents and Settings\Lucas\My Documents\Visual Studio 2005\Projects\Trees\Debug\Trees.exe : fatal error LNK1120: 1 unresolved externals

Results


Build log was saved at "file://c:\Documents and Settings\Lucas\My Documents\Visual Studio 2005\Projects\Trees\Trees\Debug\BuildLog.htm"
Trees - 2 error(s), 0 warning(s)

Eggplant Wizard

Have you tried just creating a new Console Application project from scratch and re-importing your source files, as was previously suggested? It's been a while since I've done non-.NET windows development, but it looks to me like you're linking against a bunch of unnecessary libraries that are only needed for GUI apps. You can screw with the linker settings until you're blue in the face, or you can take a minute to recreate the project.

jclast

It's been a while since I wrote C++ (and I used VC++ 6.0 so my comments may not be helpful), but why are you using a #pragma once in your .h file? Hell, why are you using #pragma once at all? It's nonstandard and not all compilers support it.

Say you're including a header file, node.h.

If you structure your .h file this way, you'll know for certain that your .h file is actually being included one time and only one time. Compilers that claim to support #pragma once have been known to screw up and cause linker problems (at least it was common in my university).

#ifndef __node_h__
#define __node_h__

// node.h code here

#endif

I have no idea if it will solve your problem or not, but it's worth a shot.

Philodox

I've been in similar situations and did my best to change the project settings to console but VS buries the GUI project settings so deeply that I doubt you could get all of them unless you know exactly what you're looking for. All in all it's just easier to recreate the project.

clsCorwin

I have recreated the project, still same results.

As far as the #pragma once issue, I've not been taught one way or the other as far as #ifndef, #pragma, etc. It's just there when I "Add class," it builds the .cpp and .h file and puts the #pragma in there. I've done projects with multiple files before and the #pragma once never caused any errors.

ecco the dolphin

Eep - I've found one problem - your SUBSYSTEM is still set to "WINDOWS", not "CONSOLE" in the original build log.

/OUT:"C:\Documents and Settings\Lucas\My Documents\Visual Studio 2005\Projects\Trees\Debug\Trees.exe" /INCREMENTAL /MANIFEST /MANIFESTFILE:"Debug\Trees.exe.intermediate.manifest" /DEBUG /PDB:"c:\Documents and Settings\Lucas\My Documents\Visual Studio 2005\Projects\Trees\debug\Trees.pdb" /SUBSYSTEM:WINDOWS /MACHINE:X86 kernel32.lib user32.lib gdi32.lib winspool.lib comdlg32.lib advapi32.lib shell32.lib ole32.lib oleaut32.lib uuid.lib odbc32.lib odbccp32.lib

See where it goes /SUBSYSTEM:WINDOWS ?

It should be /SUBSYSTEM:CONSOLE

Now, you said you've since recreated the project, so could you check to make sure that the SUBSYSTEM is set to CONSOLE by looking into your BuildLog.htm file again?

If not, try recreating the project by going:

File -> New -> Project -> Visual C++ -> Win32 -> Win32 Console Application

This should pop up a new window, go into "Application Settings"

Application Type: Console application
Additional Options: Only check "Empty Project"
Add common header files for: Don't check anything here

Finish

And add all your files again.

Re: #pragma once - it's a header protection method that's specific to Visual C++. At this stage, I wouldn't worry about it since you're just learning the language, and your programmes aren't intended to be portable. Really, at this stage, I believe that you just need to keep in mind that #pragma once won't necessarily work on other compilers.

clsCorwin

Thats how I always build my projects, Console Application/Empty Project.

Wierd, I had changed that option before, and I still got the same error. Maybe there was something else going on before I recreated it. Hmm, whatever. Thanks.