The zero flag cannot be dropped because it would be impractical if not impossible to do any kind of equality comparison or bit testing. CMP, AND, and BIT become a whole lot less useful.

The carry flag is essential for doing comparisons. How would you write "if foo < bar" without doing a CMP ...

WDC has already responded to me and pulled the download until they fix it. Kudos for taking the issue seriously!

I'm posting this as a heads-up to anyone who might happen to be thinking of installing WDCTools. Long story short, its installer deleted my PATH variable without prior warning. Here is the bug report I'm sending to WDC:

The WDCTools installer (WDCTOOLS.exe) has a serious bug. It completely ...

Thanks, guys. I think I posted in the wrong forum, though... perhaps it should be moved to the Programming forum?

I'm developing a 65816 assembler, and I've noticed an oddity with at least some other assemblers. Suppose we have this code:

bra $12

...what does it mean? Is the $12 relative or absolute? To me it makes sense that $12 is taken as an absolute address and so, assuming a PC of 0 (for the sake of ...