OSDev.org

I followed a few different OSDev Tutorials and pieced together a working "semi-kernel" (only up to GDT - no IDT yet...) a few days back and today, I went to re-assemble it and I notice that the output file is 5 bytes larger and it triple faults with a GDT error in Bochs. I had one copy of the source on a flash drive, and one copy on my HDD. I tried to assemble both and found that the file was still 5 bytes larger. Is there any way I can verify if nasm is causing the problem, or if both sets of the source code are messed up?

did you change nasm in any way? in my experience nasm is very consistent and so the tool is probably not to blame. I would highly recommend a quick crash course in git version control. use git liberally to save your stuff and use tig to view the history.