Hi,
I have recently been updating the FPU diagnostic tool to support extended precision format - while this is not quite finished yet, I have already noticed a high failure rate for Hatari vs HW and it *seems* to be related to unused bits set to 1 in source data using the 'memory exploded' extended format (resulting in INF or NaN output instead of real values). This probably isn't serious for compatibility purposes but its an example of something that only shows up when testing this format...
Anyway I'll post the new tool soon...
D