Linker error when a C++ function is called from a c file

Hello

I have  an  existing source (C++ source files)  which I wanted to convert to a SYS/BIOS based project.

main.c  file's Task_create() is calling  my application's main function, which is in C++  file.

It creates a error during linking time.

undefined first referenced                                                                                 

symbol in file

--------- ----------------                                                                                 

_taskFxn

error #10234-D: unresolved symbols remain

(taskFxn is defined in a cpp file)

How can I resolve this error?

Best Regards

JK