Multiple definition of ***

Chlaban · ‎2025-02-21

Hello,
I have a question that is completely unrelated to STM, but I believe you can help me. 
I would like to advise why I cannot use the following code and the message multiple definition comes out.
I will reduce the code to the necessary minimum.
I thought local variables in files only have local effect, can someone explain this to me? Thank you


main:
#include "A.h"
#include "B.h"
void main() 
{}

A.h:
---------
A.c:
#include "A.h"
int i;
----------

B.h:
----------
B.c:
#include "B.h"
int i;

mƎALLEm · ‎2025-02-21

Hello,

Declare int i as static:

static int i;

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View solution in original post

AScha.3 · ‎2025-02-21

Hi,

https://letmegooglethat.com/?q=avoid+multiple+definition+header+file+c

read:

https://www.quora.com/What-are-some-ways-to-avoid-multiple-inclusion-of-the-same-header-file-in-C-programming

If you feel a post has answered your question, please click "Accept as Solution".

mƎALLEm · ‎2025-02-21

Hello,

Declare int i as static:

static int i;

To give better visibility on the answered topics, please click on "Accept as Solution" on the reply which solved your issue or answered your question.
PS:
1 - This is NOT an online support (https://ols.st.com) but a collaborative space.
2 - Please be polite in your reply. Otherwise, it will be reported as inappropriate and you will be permanently blacklisted from my help.