Hare-shaped lib/log v1: logger vtable carrying one println slot,
stdlogger forwarding to a *io.stream, plus *logger globals (silent
/ default / global), setlogger, lprintln / println, lfatal / fatal.
Default sink is stderr through a private rt_syscall write callback;
graduates with #17 (cgen mod-mangle for fn labels), at which point
the rt_syscall stub disappears the same way fmt's will.
Module-scope struct/pointer-literal init isn't constexpr in cstage
emit_lets, so silent/default/global are wired lazily by ensureinit
on the first exported-fn entry (lib/temp rnginit pattern). Callers
that read the globals directly must call some lib/log fn first.
Skipped this round: printfln / lprintfln / fatalf / lfatalf and the
matching printfln vtable slot — they need a fmt {n}-placeholder
parser that isn't shipped yet. fatal / lfatal's exit(255) arm has
no test fixture (needs fork+wait for WEXITSTATUS); left as TODO.
971_log_run wraps the @test fixture under `ww run`, mirroring
970_fmt_run. make test: 54/54; bootstrap fixed-point (990-997)
holds.
Hojun-Cho
e7f173cde0