kill -l with bogus numeric signal n outputs n & 127

[okdana]

(unposted)

% kill -l 9000 8000 7000
40
64
88

That's related to this code in jobs.c:

} else {
    if (WIFSIGNALED(sig))
        sig = WTERMSIG(sig);
    else if (WIFSTOPPED(sig))
        sig = WSTOPSIG(sig);
    if (1 <= sig && sig <= SIGCOUNT)
        printf("%s\n", sigs[sig]);
    else
        printf("%d\n", sig);
}

I know 127 is kind of a special number but i don't understand why it's doing this and i feel like it's undesirable. bash behaves more like i would expect:

$ kill -l 9000
bash: kill: 9000: invalid signal specification