Wwstage's cgalloc hardcoded `CALL rt_alloc(SB)` at cgenexpr.ww:2747 and
cgenstmt.ww:647. Cstage already routes through ffi_resolve("alloc")
at cmd/w6c/cgen.c:4149 — when a fixture lacks the @symbol("rt_alloc")
decl in scope, cstage falls back to `CALL alloc(SB)` while wwstage
still emits `CALL rt_alloc(SB)`. The divergence is dormant in
ww build (combined.ww always pulls lib/os/os.ww's decl) but activates
under direct `w6c file.ww` and any other single-file path.
Replace the hardcoded line with the ffiresolve(c, "alloc") pattern
already used for user-function calls. The @symbol decl in lib/os/os.ww
is unchanged and propagates via the combine step.
Extends test/wcc/758_cgalloc_str_field.c with 4 table-driven asm rows
that compile a fixture via direct w6c (no combine) and `cmp` the
CALL <sym>(SB) line between stages. The 3 noscope rows fail without
the fix and pass with it; the withsym row pins the positive ffi-hit
path. Test count internal: 12 → 16; total make test: 132/132.
Hojun-Cho
4c51bce244