Every surviving carrier now owns its artifacts: checked mkdir/mkdtemp/
fopen acquisition, one all-exit cleanup funnel per carrier, ENOENT-
tolerant checked unlinks, exact-path deletion (rm -rf only for an
owned pid-keyed dir or a .sepwork beneath one), and cleanup failure
fails a passing carrier without overwriting its diagnostic. In the
same pass the carriers adapt to the driver contract this branch lands:
--sep and WW_PKGCACHE are gone, -S and the /tmp/ww_run_<pid> scratch
contract are asserted, and rows whose runtime or reject coverage moved
to test/wcc/data fixtures or test/lang @test owners are trimmed to the
byte/artifact/diagnostic observations only they can make.
Repair and adaptation ride together because most files interleave both
in the same hunks; splitting would manufacture intermediate carrier
states that never existed and cannot run against either driver.
The .wwi (separate-compile interface) producer could not serialize an
exported def whose initializer is a struct/array literal (N_STRUCTLIT/
N_ARRLIT) — `export def f64info: floatinfo = floatinfo{...}` aborted with
"unhandled const-expr node kind 15". Such a def is a DATA-global per the
#52 model, so its value lives once in the defining package's .o; the
interface needs only the type+symbol. Emit a value-less prototype
`export def X: T;` for aggregate-initializer defs; scalar fold-eligible
defs keep their value (the importer const-folds those). The parser gains
an optional-init arm so the importer can parse the prototype — value-less
`def X: T;` is now legal in any source, symmetric with the existing
bodyless-fn prototype `fn f();` (USER ruling: unconditional; a value-less
def with no defining .o is a loud undefined-symbol error at link, never
silent). Both stages; producer + parser fold into one commit (the
producer's output is unparseable without the parser arm).
M3-tail commit-6 prerequisite #2 (surfaced by the c6 scout). The
aggregate-def-field const-fold boundary is documented inline (#71). Gate
989_sepstructdef_run proves struct+array exported defs sep-build, link,
and run via external DATA refs, cs==ww, with a value-less .wwi.
