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GeneralRe: Floating point conversion Pin
Still learning how to code5-Dec-15 1:29
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AnswerRe: Floating point conversion Pin
CPallini4-Dec-15 0:30
mveCPallini4-Dec-15 0:30 
GeneralRe: Floating point conversion Pin
k50544-Dec-15 5:21
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QuestionIEEE 754-1985 Pin
enhzflep4-Dec-15 6:43
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AnswerRe: Floating point conversion Pin
S.T.K8-Dec-15 4:19
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QuestionComboboxx issue in MFC Pin
Amrit Agr3-Dec-15 3:48
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SuggestionRe: Comboboxx issue in MFC Pin
Richard MacCutchan3-Dec-15 4:50
mveRichard MacCutchan3-Dec-15 4:50 
QuestionVisual Studio error LNK2005: variable XXX redefined in xxx.obj Pin
Javier Luis Lopez26-Nov-15 1:09
MemberJavier Luis Lopez26-Nov-15 1:09 
I tried to isolate the problem

It appears when a global variable is declared at the .h header file and the header file is called from 2 or more cpp files, as example I tried to link the following 3 files:

//==File: header.h 
#pragma once
#include <stdio.h>

int variable;
//==end header.h

//==File: main.cpp
#include "header.h"
void main()
{
	variable=0;
}
//==end main.h

//File: source2.cpp 
#include "header.h"

void change()
{
	variable=0;
}
//==end source2.cpp


Then the following LINKER error appear:
1>source2.obj : error LNK2005: redefined "int variable" (?variable@@3HA) in main.obj

The only way I could "fix" the problem is in project properties> linker>command line add:
/FORCE:MULTIPLE
Unfortunately it can hide possible problems

I think the problem is that the #pragma once does not work.
It does not work also to define a constant and use #ifndef to avoid reading 2 times.
AnswerRe: Visual Studio errYou should declare it or LNK2005: variable XXX redefined in xxx.obj Pin
Richard MacCutchan26-Nov-15 1:24
mveRichard MacCutchan26-Nov-15 1:24 
GeneralRe: Visual Studio errYou should declare it or LNK2005: variable XXX redefined in xxx.obj Pin
Javier Luis Lopez26-Nov-15 1:53
MemberJavier Luis Lopez26-Nov-15 1:53 
GeneralRe: Visual Studio errYou should declare it or LNK2005: variable XXX redefined in xxx.obj Pin
Richard MacCutchan26-Nov-15 2:11
mveRichard MacCutchan26-Nov-15 2:11 
GeneralRe: Visual Studio errYou should declare it or LNK2005: variable XXX redefined in xxx.obj Pin
Javier Luis Lopez26-Nov-15 4:29
MemberJavier Luis Lopez26-Nov-15 4:29 
GeneralRe: Visual Studio errYou should declare it or LNK2005: variable XXX redefined in xxx.obj Pin
Richard MacCutchan26-Nov-15 5:26
mveRichard MacCutchan26-Nov-15 5:26 
AnswerRe: Visual Studio error LNK2005: variable XXX redefined in xxx.obj Pin
Daniel Pfeffer26-Nov-15 7:34
professionalDaniel Pfeffer26-Nov-15 7:34 
GeneralRe: Visual Studio error LNK2005: variable XXX redefined in xxx.obj Pin
CPallini26-Nov-15 22:09
mveCPallini26-Nov-15 22:09 
GeneralRe: Visual Studio error LNK2005: variable XXX redefined in xxx.obj Pin
Richard MacCutchan26-Nov-15 23:23
mveRichard MacCutchan26-Nov-15 23:23 
GeneralRe: Visual Studio error LNK2005: variable XXX redefined in xxx.obj Pin
Daniel Pfeffer28-Nov-15 7:51
professionalDaniel Pfeffer28-Nov-15 7:51 
AnswerRe: Visual Studio error LNK2005: variable XXX redefined in xxx.obj Pin
«_Superman_»29-Nov-15 19:46
professional«_Superman_»29-Nov-15 19:46 
GeneralRe: Visual Studio error LNK2005: variable XXX redefined in xxx.obj Pin
Richard MacCutchan29-Nov-15 23:22
mveRichard MacCutchan29-Nov-15 23:22 
GeneralRe: Visual Studio error LNK2005: variable XXX redefined in xxx.obj Pin
«_Superman_»30-Nov-15 0:07
professional«_Superman_»30-Nov-15 0:07 
GeneralRe: Visual Studio error LNK2005: variable XXX redefined in xxx.obj Pin
Richard MacCutchan30-Nov-15 0:38
mveRichard MacCutchan30-Nov-15 0:38 
GeneralRe: Visual Studio error LNK2005: variable XXX redefined in xxx.obj Pin
«_Superman_»30-Nov-15 0:40
professional«_Superman_»30-Nov-15 0:40 
GeneralRe: Visual Studio error LNK2005: variable XXX redefined in xxx.obj Pin
Richard MacCutchan30-Nov-15 1:01
mveRichard MacCutchan30-Nov-15 1:01 
Questionc langugae Pin
ravi siriki23-Nov-15 2:58
Memberravi siriki23-Nov-15 2:58 
AnswerRe: c langugae Pin
David Crow23-Nov-15 3:38
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