g++ linking problem: undefined reference to Function

[fidogenial]

Hi All,

I am trying to add some function to the c++ project (calling function) and the called function are in C. And i am getting error "undefined reference to "Hello(int,int)" " while linking. It is compling correctly. It is linking to header file mention in the calling function. This header file has definition to the c - called function.


Do you thinking having c files into C++ project will be a problem ?
Should I remove <stdio.h> in c files ?

Please let me know your suggestions.

Thanks
fido

[markcole]

Calling c functions from a c++ program is no problem at all. Post the code and we might be able to spot what is wrong.

[Rubberman]

In your C++ code, you need to indicate to the compiler that the external function uses C-linkage. That is the purpose of the compiler directive 'extern "C"'. Example:

// C++ source file, xyz.cpp
extern "C" void cfunc(void);
void xyz::somefunc(int)
{
    // Do some stuff
.
.
.
    cfunc(intval);
}