The wcc test drivers ran `ww build <bare-/tmp src>` with no -o, so the
compiler's <stem>.sepwork scratch landed beside the source and was never
cleaned: unbounded /tmp growth (2195 stale dirs observed) that fills tmpfs
and fabricates phantom test failures + silent harness aborts, and for
in-repo fixture builds leaked .sepwork into the tracked tree.
Each leaking build now writes its source + output inside a per-invocation
tmpdir, passes -o <tmpdir>/<stem> so the .sepwork lands inside it, and
rm -rf's the tmpdir on every exit path -- including fopen-fail and the
expected-fail reject builds (scratch is mkdir'd before the build can fail).
`ww run` and explicit-`-o`/byte-id helpers are left as-is; the 990/993
byte-id comparison logic is byte-for-byte unchanged.
Two items filed separately (this commit holds the no-Makefile / no-main.c
rail):
- #13: a stale <src>.s byte-id readback (749) silently no-ops since
separate-compile emits .s to <ostem>.sepwork/__root.s; documented inline.
- #14: build-system Makefile recipes build selfhost/cmd/*/main.ww with no
-o and leak main.sepwork in-tree (bounded, gitignored; own commit).
One concern -- sepwork leak hygiene -- across 228 drivers; uniform
transform applied per-file and two-round reviewed. make test: all 402
passed, zero net-new /tmp scratch, zero test-driven in-repo .sepwork.
A let-global slice or str passed by value as an argument was silently
field-dropped by wwstage: pushargsrev's global branch had only the #150-A
struct arm, and wwstage's nodeisslice/nodeisstr are local-keyed (false for
a global), so a global slice/str ident fell to the scalar single-PUSHQ,
pushing one of the three header words {ptr,len,cap} -> the callee read
garbage for .len/.cap. cstage was already correct.
wwstage-only, caller-side only (slice/str params already received
correctly). A global slice/str arm in pushargsrev, type-keyed on
tichase(arg.type_).kind, with two arms byte-matching cstage's two distinct
sequences -- str via cgslicehdr (CX-base, cgen.c:1866), slice per-word
(BX-base, cgen.c:9124). Gate is isletvar-only (a def has no name(SB)
holder; cstage const-folds it -- def-str/slice-by-value is the residual
task #21). cstage unchanged (w6c md5 unchanged); byte-id 990-997 8/8,
no lib pin flips. test/wcc/829 table-driven, byte-id per type.
