validname0 looks like it is trying to be too clever. A better version of the first if statement would be:
if((ulong)name < KZERO) { validaddr((ulong)name, 1, 0); if(!dup) print("warning: validname called from %lux with user pointer", pc); ename = vmemchr(name, 0, 1<<16); } else ename = memchr(name, 0, 1<<16); Russ