I was using the official 2.4-x64 build (msvc), and also a 2.4.1-x86 build (gcc), both were exhibiting the same issue. I was not able to reproduce it in 2.4.4-x86, but was encouraged to submit this ticket anyway. These are all Windows builds. I am running this on Windows 8 x64.
Using default settings in Vice, all I have to do is this (in this order):
- When BASIC loads up, enter the Monitor.
- Use the command "BREAK STORE". Any address will suffice.
- Close the Monitor.
- Attempt any floating-point arithmetic.
This happens on x64, x64sc, x128, xcbm2, xcbm5x0, xpet, xplus4, and xvic. It does not happen on x64dtv.
A hard reset does not fix it. The application itself needs to be restarted. If you save the state and then reload the state in a new instance of the program, the bug is also gone. Because the bug does not persist through save state, I did not include one.