The lone js opt-in-JIT residual was async/await_in_loop, which failed to PARSE
under JIT ("Unexpected token: op '<'" on `i < 5`) while passing on CEK. The js
exclusion was "js-*", but the recursive-descent parser is the jp-* namespace
(75 functions in lib/js/parser.sx) — only the lexer/transpile/runtime are js-*.
So the parser was left JIT-eligible and a jp-* function miscompiled this
construct (the long-standing parser-miscompile class).
Fix: extend the js exclusion to "js-* jp-*" so the parser is interpret-only too,
matching how every other guest's front-end is handled. js conformance under
SX_SERVING_JIT=1 is now 148/148, == CEK.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Enabling the epoch serving-mode JIT globally regressed continuation-based guest
interpreters (the epoch mode is the shared command channel every loop's
conformance runner uses). Two-part fix:
1. SAFE DEFAULT GATE. register_jit_hook in the persistent server branch is now
opt-in via SX_SERVING_JIT=1 (default OFF). Default behaviour is unchanged
(no JIT in epoch serving) → zero regression for sibling loops. The
content/Smalltalk page server opts in.
2. GENERAL FIXES + per-guest interpret-only declarations:
- callable? (sx_server/run_tests/integration_tests/mcp_tree) now accepts
VmClosure. A JIT-compiled higher-order function returns its inner closure
as a VmClosure; callable? previously rejected it, so scheme-apply's
(callable? proc) guard failed with "not a procedure: <vm:anon>".
- jit-exclude! gains a trailing-"*" namespace-prefix form
(Sx_types.jit_excluded_prefixes), the robust way to mark a whole guest
interpreter interpret-only (a name-list misses functions in extra files —
it left erlang's vm/dispatcher JIT'd and 13 tests short).
- Per-guest exclusions in each guest's runtime.sx:
scheme "scheme-*" "scm-*" erlang "er-*" "erlang-*"
prolog "pl-*" common-lisp "cl-*" "clos-*"
js "js-*" haskell "hk-*"
Verified under opt-in JIT (== CEK, no hang): smalltalk 847/847, scheme/flow
166/166, erlang 530/530, prolog 590/590, apl 152/152, js 147/148. Residual
(documented, protected by the default gate): common-lisp 6 fails in advanced
suites (parser-recovery/debugger/CLOS/MOP). lua (0/16) and tcl (3/4) fail
identically on CEK — pre-existing, not JIT. run_tests --jit/no-jit unchanged.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
The OCaml epoch-protocol printer serializes raw SX dicts. JS object literals
now carry __proto__ / __js_order__ bookkeeping that points into Object.prototype,
a complex dict containing lambdas that close over Object — the printer
recurses indefinitely and hangs.
js-display walks the value once, dropping any dict key that matches the
__name__ dunder convention. js-eval calls it on its return value so the
output is the user-facing shape only. Restores 587/593 passing (up from
191/593 post-merge and 492/585 pre-merge) — the surviving 6 failures are
legitimate pre-existing test mismatches (illegal return/break/continue,
parseFloat float vs rational, escaped backtick).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
