Hojun-Cho
ff333ce62d
57 piecewise stderr diagnostics in the checker spelled out os.write(2, m.ptr, NNu64) with hand-counted byte literals. Replace the 38 hand-counted literal sites and 19 var sites with a tool-local cerr(m: str) helper that takes .len off the str, eliminating the off-by-one hazard. All 38 prior hand-counts were already correct, so stderr is byte-identical. cerr lives in check.ww (not err.ww, which ports err.c for the dead C-driven path); regen w6c + wwdump combined.ww.