simon/jolt

History

Yogthos a3e2365217 Recover TCO-elided frames in uncaught-error stack traces On the eval path nothing registers a source map, so jolt-backtrace-string dropped every walkable frame and printed no trace at all. Keep any named, non-plumbing continuation frame (rendered as a bare name when unmapped) so a runtime error shows the surviving non-tail spine — "print what is available". Add an opt-in tail-frame history behind JOLT_TRACE for the frames TCO erases. Each compiled fn records itself on entry into a bounded ring-of-rings, MIT Scheme's "history" shape: the outer ring holds one rib per non-tail subproblem, each rib a small inner ring of the tail-calls made at that level. A tight tail loop churns one rib instead of flushing the spine, so the non-tail caller context survives and total space stays bounded. The reporter prefers this history over the continuation when it's present, and resets it per top-level form so an error's trace isn't padded with earlier REPL frames. The emitter marks a tail call with (jolt-trace-mark! #t) so the runtime routes the callee into the current rib vs a fresh one; a tail? dynamic var tracks tail position (cleared by default, passed through if/do/let/loop/fn-body). It's all gated on trace-frames?, which compile-eval turns on for JOLT_TRACE and emit-image/`jolt build` force off — so non-trace emitted output is byte-identical (prelude unchanged, seed re-minted), and a built binary carries no per-call cost.		2026-07-04 15:00:52 -04:00
..
image.ss	Recover TCO-elided frames in uncaught-error stack traces	2026-07-04 15:00:52 -04:00
prelude.ss	Clojure 1.13 parity: req!, checked-keys destructuring, keyword array maps	2026-07-04 10:18:51 -04:00
README.md	Docs: Chez-only, drop the Janet-era references and obsolete migration notes	2026-06-22 09:05:35 -04:00

README.md

Chez bootstrap seed

These two files are the bootstrap compiler for jolt — the seed that makes the build self-hosting:

prelude.ss — the clojure.core prelude (all tiers + clojure.string/walk/ template/edn/set/pprint) as Scheme def-var! forms.
image.ss — the compiler image (jolt.ir + jolt.analyzer + jolt.backend-scheme) as Scheme def-var! forms.

Both are generated, not hand-written. They are checked in because a fresh checkout must be able to build jolt-on-Chez using only Chez: host/chez/bootstrap.ss loads this seed, then rebuilds the prelude + image from the .clj/.ss sources via the on-Chez compiler (read → analyze → emit, all on Chez). The seed is a joint byte-fixpoint: rebuilding from an up-to-date seed reproduces it exactly. make selfhost (host/chez/selfcheck.sh) runs host/chez/bootstrap.ss and diffs the rebuilt artifacts against the checked-in seed.

Re-minting

When the seed sources change (the core tiers, the compiler namespaces, the host contract, the reader, emit-image.ss), the seed drifts and make selfhost fails. Re-mint it by running host/chez/bootstrap.ss and writing the freshly rebuilt prelude/image back to host/chez/seed/prelude.ss / host/chez/seed/image.ss, then commit the refreshed files.