Just because KDE4-era software has been deprecated by the KDE-FreeBSD team in the official ports-repository, doesn't mean we don't care for it while we still need to. KDE4 was released on January 11th, 2008 -- I still have the T-shirt -- which was a very different C++ world than what we now live in. Much of the code pre-dates the availability of C++11 -- certainly the availability of compilers with C++11 support. The language has changed a great deal in those ten years since the original release.
The platforms we run KDE code on have, too -- FreeBSD 12 is a long way from the FreeBSD 6 or 7 that were current at release (although at the time, I was more into OpenSolaris). In particular, since then the FreeBSD world has switched over to Clang, and FreeBSD current is experimenting with Clang 7. So we're seeing KDE4-era code being built, and running, on FreeBSD 12 with Clang 7. That's a platform with a very different idea of what constitutes correct code, than what the code was originally written for. (Not quite as big a difference as Helio's KDE1 efforts, though)
So, while we're counting down to removing KDE4 from the FreeBSD ports tree, we're also going through and fixing it to work with Clang 7, which defaults to a newer C++ standard and which is quite picky about some things. Some time in the distant past, when pointers were integers and NULL was zero, there was some confusion about booleans. So there's lots of code that does
list.contains(element) > 0 .. this must have been a trick before booleans were a supported type in all our compilers. In any case it breaks with Clang 7, since
contains() returns a
QBool which converts to a nullptr (when false) which isn't comparable to the integer 0. Suffice to say I've spent more time reading KDE4-era code this month, than in the past two years.
However, work is proceeding apace, so if you really really want to, you can still get your old-school kicks on a new platform. Because we care about packaging things right, even when we want to get rid of it.