Both fail with a "too much recursion" error message during start up.
I'm guessing the feature confuses them about the depth of the stack somehow.
Tested on 12.0-STABLE r351060.
They both work fine with the stackgap sysctls set to 0.
And they both have been working fine with the other ASLR features on ever since this was committed to 12-STABLE BTW.
hm, according to https://wiki.freebsd.org/ASLR the base ntpd also doesn't like stackgap..