The old code would truncate element names to DIRSIZ and leave out
NULL.  The new ns code, however, depends on NULL terminated strings.

should be much faster, though no more scalable

user and kernel crange.c are identical

If we don't -include compiler.h it's important to always include
the header with the attribute defines before they are used.
Otherwise the compiler will silently "fail" by defining variables
named the attribute define (e.g. __mpalign__).  Another option
is to remove the attribute defines, but I kind of like them.

Each core's gc thread free elements on the tofree list