Describe the bug
A clear and concise description of what the bug is.

To Reproduce
Steps to reproduce the behavior:

1. Build a unit test where you are utilizing the googletest library for performing unit tests on your code.
2. Launch gdbgui from inside the root dir of your project containing your source code.
3. In gdbgui, add an absolute path to your built unit test executable and click the "Load Binary" button.
4. The gdb window says Function "main" not defined.

Expected behavior

I expected the source code to show up in gdbgui, and to be able to debug the program. Even if I manually use the gdb command file /my/path/to/executable inside gdbgui and then try to run it, it won't work in gdbgui. But, in plain old gdb in the terminal, I can run and debug the whole thing just fine.

Screenshots

Please complete the following information:

• OS: Ubuntu 18.04
• gdbgui version (gdbgui -v): 0.13.2.1
• gdb version (gdb -v): GNU gdb (Ubuntu 8.1-0ubuntu3.2) 8.1.0.20180409-git
• browser [e.g. chrome, safari]: chrome
• python packages (pip freeze):

Additional context
NA