todo: tick the parity runner; zc0 follow-ups it found

1 files changed, 3 insertions, 1 deletions

diff --git a/TODO.md b/TODO.md
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@@ -158,11 +158,13 @@ the final full suite stays at the very end whatever its size.
 - [ ] packed byte strings and `u`/`m`/`d` in zc0: match the self-hosted compiler's `bstr` support, and treat `u`, `m`, `d` as ordinary names (a recast is the letter directly followed by `*`; tags are accepted and ignored), keeping zc0's genome image byte-identical.
 - [ ] write `docs/SPEC.md`, the language specification, from the self-hosted compiler as the reference, with the zc0 subset marked and every disagreement between prose and code listed.
 - [ ] verify both compilers against `docs/SPEC.md` with a fresh agent: one test program per rule, run on both, every deviation reported and triaged.
-- [ ] a `make parity` runner that compiles the zc0-compatible programs (and the genome sources) with zc0 and with the self-hosted compiler, runs both images and compares output, so the two front ends can't disagree silently again (the `&&`/`||` precedence bug).
+- [x] a `make parity` runner that compiles the zc0-compatible programs (and the genome sources) with zc0 and with the self-hosted compiler, runs both images and compares output, so the two front ends can't disagree silently again (the `&&`/`||` precedence bug). (`src/tools/parity.sh`, `make parity`; by-design differences in `tests/parity.known`.)
 - [x] c typedefs: `typedef T name;` declares a type alias, including pointer, array and function types, usable everywhere a type is, shown in hovers.
 - [ ] split `src/compiler/compiler.zc` into files by phase (lexer, types, expressions, statements, analyzer, declarations, check mode, image), listed in order in one place; the concatenation must reproduce the old file exactly so every image stays byte-identical. update every consumer: the makefile, tool scripts, the language server's embedded copy, tests, docs.
 - [ ] a cross-reference report: for every global of the compiler, the functions that write it and the ones that only read it, built from the language server's references so scoping is exact, runnable as a script and in ci so a new writer of core state shows up in review.
 - [ ] group the compiler's parallel per-local arrays (`lname`, `ltype`, `lstate`, `lhome`, `lown`, ...) into one record per local with accessor functions, so a branch snapshot is one block copy and each field's invariant is written once next to the record. then do the same for symbols and types. the genome must keep reaching its fixpoint, and the analyzer's behavior must not change (all rejection suites and the program checks identical).
+- [ ] zc0 has no `?:`; add it so parity covers conditional expressions, and grow zc0's subset where it is cheap (structs and enums are the largest group of programs parity skips today).
+- [ ] a run-only image accepts `void main()` from zc0 but the self-hosted compiler rejects it against `run.zc`'s `int main();` prototype; make the two agree.
 - [ ] continue removing `unchecked` from the remaining runtime boundaries by teaching the analyzer the missing ownership and drop contracts; document any irreducible low-level escapes. the compiler, standard library and lsp no longer disable checking for their functions. status, from a trial that was reverted: with `unchecked` removed, `copy_w` and `fill_w` pass the analyzer once their gate stores go through `syscall(SYS_COPY, ...)`, `dgrow` once `w[-2] = it` becomes `own(w, it)`, `dpush` once `own(x, h[2])` comes before the store, and `dnew` as is. but the checked versions changed run-time behavior: 7 of the 87 program checks in `tests/test.sh` failed (closure cells, the proved-loop bounds check) and `tests/programs/share.zc` hung with a checked `cons`. so checked code in these functions inserts cleanup the runtime can't afford, and each one needs its contract taught to the analyzer, not just a rewrite that compiles. `free`, `recycle`, `recycle_leaf` and `gc` are the allocator and collector that the analyzer's own cleanup calls, so they stay unchecked and need to be documented as the irreducible escapes. `src/lib/actor.zc` has about 20 more.
 - [ ] document the public standard-library apis with concise descriptions of behavior, parameters, ownership and return values where applicable; update reference and learning entries, add executable examples and record implemented changes in history; keep prose lowercase and verify docs appear in hovers.
 - [ ] revise diagnostics, comments and learning/reference prose using professional compiler documentation guidance, preserving lowercase and adding message regressions.