HPGCC 2.0 and Programmer's Notepad

[Helix]

I'm currently learning C.
I can run small programs on my HP 50g with HPGCC 2.0 and Programmer's Notepad, as shown in this page.

Compilation works fine with the "Make this .hp" tool, as long as there is only one file to compile.
But if I want to create a project with a function in a second file, say myfunction in myfile.c, and with myfile.h for the header, then I get the error: "undefined reference to 'myfunction'.
It seems that the "Make this .hp" tool doesn't link the files.

This project works perfectly with Code::Blocks, so I suppose my code is correct.
Is there a way to compile such a project with the Programmer's Notepad?