C Code linking to C++ in CLion not working

Question

I know there are huge amount of posts, but going through lots of them i found nothing that worked.

I want to include some .h and .c files into my C++ file.

Clicking into the method in CLion it redirects me to that foo.h file, but in the end it's not working with following message:

Undefined symbols for architecture x86_64: "_fooFct", referenced from: _main in main.cpp.o ld: symbol(s) not found for architecture x86_64

foo.h

 void fooFct();

foo.c

void fooFct(){
    /* do some stuff here */
 }

main.cpp

#include <iostream>

extern "C"
{
    #include "clibraryFolder/header/foo.h"
}

int main() {
    fooFct();
    return 0;
}

CMakeLists.txt

 cmake_minimum_required(VERSION 3.6)
 project(newcsample)

 set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11")

 set(SOURCE_FILES main.cpp)
 add_executable(newcsample ${SOURCE_FILES})

But I don't want to include the C files in the CMakeFiles.txt. Is there another way doing this than by editing the CMakeFiles?

What does your CMakeLists.txt file look like? Does it list foo.c in the source list? — Some programmer dude
you are declaring the fooFct() function, but you are not linking in its definition: the latter should be in the object file created for foo.c, are you linking it as well? — Luca Cappa
you mean something like gcc -c Cfile.c, gcc -shared -o libCfile.so cFile.o, c++ -L/somehwere -Wall main.cpp -o main -lCfile? Nope, I wanted to fully get it done by CLion. Or isn't it possible? — flyOWX

Seek Addo Seek Addo · Accepted Answer · 2017-02-16T19:52:01

make the following changes in your CMakeLists.txt file

 cmake_minimum_required(VERSION 3.6)
 project(newcsample)

 set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11")

 set(SOURCE_FILES main.cpp foo.c) #all .cpp files and .c files here
 add_executable(newcsample ${SOURCE_FILES})

and if the #include you can specify only the current directory if the .h file is there.

C Code linking to C++ in CLion not working

1 Answers