The macro UT_LIST_INIT() zero-initializes the UT_LIST_NODE.
There is no need to call this macro on a buffer that has
already been zero-initialized by mem_zalloc() or mem_heap_zalloc()
or similar.

For some reason, the statement UT_LIST_INIT(srv_sys->tasks) in
srv_init() caused a SIGSEGV on server startup when compiling with
GCC 7.1.0 for AMD64 using -O3. The zero-initialization was attempted
by the instruction movaps %xmm0,0x50(%rax), while the proper offset
of srv_sys->tasks would seem to have been 0x48.