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C program multiple definition error during linking time

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# 8  
Old 03-27-2013
Don't do the following. Don't try to initialize the external variable outside of a function.
Code:
i = 20;
int main()

Even if it worked, it's extremely confusing. What's the point or advantage, anyway? Do you want to have two external vars with the same name? If you just want to set the value to 20, do it inside a function.
# 9  
Old 03-27-2013
Quote:
Originally Posted by royalibrahim
Why I have to allocate a memory for i (declaring an int i) in the global scope in file2.c to get rid of this problem?
You're lying to the compiler by telling the compiler it exists (extern int i) but not actually instantiating it anywhere. The extern just tells it to look for it somewhere else, but you must instantiate it in one and only one file.
# 10  
Old 03-27-2013
Quote:
Originally Posted by alister
Your analysis is incorrect. There are no versions of i which are local to a block (function or otherwise). All of those identifiers refer to the same externally-linked, global storage allocation.

Regards,
Alister
Good point alister...after dotting my i's i realize that all roads lead to the same i...but the op should be educated on how not to write obfuscated code.
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