Version:           2.0.4 (using KDE 3.5.4, Gentoo)
Compiler:          Target: i686-pc-linux-gnu
OS:                Linux (i686) release 2.6.17-gentoo-r7

kcalc cmp function only compliments lower 32-bits. Basically kcalc has supported > 32-bits for a while, it seems that CMP is a function is did not transition correctly.

steps to reproduce:

open kcalc
set to hex mode
enter: FFFFFFFFFFFFFFFF
hit cmp
result is: FFFFFFFF00000000
should be: 0000000000000000

hitting cmp again confirms the behaviour by toggling the lower 32-bits back to F's

I recognize that since kcalc now attempts aribtrary precision, defining cmp is tough (how many F's to we append to the end since a positive nubmer basically has infinite 0's...)

Well the "correct" solution is not to litterally compliment, but instead take advantage of 2's compliment notation:

CMP in 2's compliment is exactly equivalent to negating the value then subtracting 1

for example:


4d2 hex (1234 in decimal) has the following value when complimented:
0xFFFFFFFFFFFFFB2D (-1235 in decimal)

so to properly implement CMP with arbitrary precision, simply negate the value, then subtract one from that. Obviously the result will be truncated in HEX view since that mode can only display 64-bits, but it will be correct. This should work correctly regardless of the number of bits supported and is trivial to implement.

Evan Teran