Makefile sets WW_W6C=$(BIN)/w6c_ww so `make`, `make test`, and
`make demo` all use the ww-built backend. With the wwstage cgen
fixes in selfhost/cmd/wcc/ the demo no longer needs to dodge:
- bug #1+#2 (global addressing): symbol interner indexes
sym_off / sym_len / sym_blob directly. No `let blob = sym_blob;`
aliasing.
- bug #3 (chained non-pointer sub-struct field): not retired here
(lexer.cur is still flattened) but the cgen now handles the
shape; un-flattening is cosmetic.
- bug #4 (f64 through every boundary): vfloat writes p.fval = v
directly; promote_v's FLOAT branch is one assign; to_f64 reads
v.ival as f64 / v.fval directly. Drops fbuf, FVAL_OFF, copybytes.
- bug #7 (xs[i].field): builtins write xs[0].kind / xs[0].car
directly; no `let p = xs[0];` first.
lisp_test still 101/101.
CLAUDE.md marks each historical bug as retired or still load-
bearing; #6 (slice-len in tagged-union return) and #8 (f64
compound assign) are the remaining shapes to avoid.
Demo program that lives entirely on lib/* and libwwrt.a — no @symbol
FFI of its own. The interpreter sits in lispcore.ww (exports for the
test driver); lisp.ww is a 3-line entry that calls lispcore.repl().
Language surface: integers, floats, symbols, strings, lists, lambdas
with closures, define / set! / if / quote / let / begin, recursion
(fact / fib / ackermann / gcd), map / filter / reduce as user code.
REPL is line-buffered: each read tries to parse one top-level form,
asks for more on "unterminated list", evaluates and prints, then
shifts consumed bytes off the front of the buffer. Lookahead-aware —
the parser primes one extra token so we shift to L.curstart, not
L.pos, otherwise the first byte of the next form gets eaten.
lisp_test.ww exec'd as a regular binary (ww test drops -I in single-
file mode); 66 probes cover arithmetic, lists, closures, recursion,
errors. test_*.lisp drive the live REPL through `make demo`.
The wwstage cgen still mis-lowers a handful of patterns at this
shape of program — top-level array indexing, global-ptr deref,
two-level field stores, f64 routing through *T, alloc(structlit{})
for f64/str fields, (slice | E) returns, xs[i].kind chains, f64
compound assigns. Each workaround is annotated at its use site;
the full taxonomy is in examples/lisp/CLAUDE.md.