Today when building K 5.0 on Debian Jessie, I got this compiler warning that I don't remember seeing before:
CC (gcc) [M domain.so] domain.o domain.c: In function 'w_lookup_domain': domain.c:222:5: warning: 'prefix' may be used uninitialized in this function [-Wmaybe-uninitialized] if(prefix) ^
-- Juha