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Dev C++ linker errors, undefined reference

You may want to investigate makefiles. Then you can use your favorite editor and still write modular code the correct way.

I just had a glance at how to write makefiles. Looks messy(will look into that later). So opened Dev C++ instead, and tried to work with projects for the first time in DevC++( used visual C++ projects bfor though). The program compiles without error but i get errors while linking, saying undefined reference to xyz. Obviously the linker is not finding the definitions of the declared functions. I did include the .cpp files containing the definitions in my project, but still getting the same errors. What should i do?

Asif_NSU
Posting Whiz
353 posts since Apr 2004
Reputation Points: 113
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>What should i do?
Post a reply to the thread that this question is concerning rather than starting a new one so that we have a clue what you're talking about. ;)

Narue
Bad Cop
Administrator
15,460 posts since Sep 2004
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I can't see your computer, but it sounds like you have a missing source file in your project list.

[IMG]http://img140.exs.cx/img140/3929/devc3ft.th.gif[/IMG]

You may need to add the file containing the definition the linker needs.

[IMG]http://img140.exs.cx/img140/7249/devc29xk.th.gif[/IMG]

I just had a glance at how to write makefiles. Looks messy

Yeah, makefiles are their own special little hell. But if you get up there on the learning curve they can be useful far beyond just working with code.

Dave Sinkula
long time no c
Team Colleague
5,058 posts since Apr 2004
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Trust me Dave, i did attach each and everyfile file required for the project. Like if I used Linked list i added both linkedlist.cpp and linkedlist.h to the project. Still the linker reports undefined reference to linkedlist methods.

Asif_NSU
Posting Whiz
353 posts since Apr 2004
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Where is the original thread. I might be able to have a look...

1o0oBhP
Posting Pro in Training
445 posts since Dec 2004
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Where is the original thread. I might be able to have a look...


The original thread deals with smthg totally different :)

Asif_NSU
Posting Whiz
353 posts since Apr 2004
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Dev-C++ creates a new makefile every time it compiles. Messing with the old one is futile, it gets overwritten.

vegaseat
DaniWeb's Hypocrite
Moderator
5,986 posts since Oct 2004
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Trust me Dave, i did attach each and everyfile file required for the project. Like if I used Linked list i added both linkedlist.cpp and linkedlist.h to the project. Still the linker reports undefined reference to linkedlist methods.

Execute -> Rebuild All should fix it.

Looben
Newbie Poster
12 posts since Dec 2006
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Execute -> Rebuild All should fix it.


I guess his problem would have been solved by now :mrgreen:

SpS
Posting Pro
599 posts since Aug 2005
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exa of class i'm assuming you are using

class c
{
public :
 class a * ac;
 class b * bc;
 c ( const c& );
 ~c(void);
};

/* source file */
c::c(const c&) { /* */ };
c::~c(){/**/};

/******************/
/* making a global declaration should resolve your undefined reference */
/*****************/
a * ac;
b * bc;
draike
Newbie Poster
1 post since Feb 2010
Reputation Points: 9
Solved Threads: 0
 

Try this solution:
Donot put the implementaion of the each function in file
but put it in header file under the class definition and remove the implementaion file

MOHAMEDMAGDY
Newbie Poster
1 post since Jul 2010
Reputation Points: 10
Solved Threads: 0
 

I am facing linker error in Dev-Cpp using functions line,setcolor etc...
help me out

sagarsindwani
Newbie Poster
1 post since Jul 2010
Reputation Points: 10
Solved Threads: 0
 

This article has been dead for over three months

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