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12435 Discussions

Nios II Eclipse "undefined reference to"

Honored Contributor II

Hi all, 


I've just downloaded Quartus 13Sp1. I'm having a 3 day issue with eclipse and I was hoping the support pack may have provided the solution, unfortunately it did not! The problem is when i compile my project in Eclipse I get the following error.  


I've searched high and low, tried the linker fix where I added -lm to 'project'\niosII application properties\Linker flags - perhaps I'm doing it wrong. 

I've examined my code, it compiles when I do not include [ //xxxx ] the lines of code causing the error. 

I appreciate this may be a stupid question to the more experienced members, but I'm at my wits end with it. 

Eclipse is quirky so I'm always sure to, save all changes. Then regenerate/clean build and finally build the bsp. 

And again, clean build and build the project. 


If I go project properties/C/C++ General/Paths and Symbols - the included directories are shown below  


The next tab Symbols is populated. A possible issue may be the Libaries and Library Paths tabs are both empty.  

Source Location conatain folder /'project' 


The code itself: I have my main.c program and included two header files. The functions causing the issue is contained in a header file. The main.c has include"xxxxx.h" for both header files but I keep getting the errors. 


The following article seems to be well on the buck but no joy again 

Perhaps I'm overlooking or doing something wrong, any help or tips would be much appreciated. 


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3 Replies
Honored Contributor II

Hi, try : right click on your project, "rebuild index"

Honored Contributor II

Thanks for taking the time to reply. 

No joy with that I'm afraid :/

Hello,Did you figure this problem out?