The source loader sets the current ns and registers :as aliases per file. The
build flattened every app namespace into one image with no such markers, so all
app forms ran under the last-set ns ("user"). Two breakages followed, both only
in a built binary:
- defmulti/defmethod resolve their target var through chez-current-ns, so they
registered the multifn under "user" while compiled var-derefs used the baked
ns — the multifn the app saw was uninitialized ("not a fn nil" on dispatch).
- a quoted alias-qualified symbol (a (defmethod ig/foo …) on an aliased multifn)
resolves its ns through chez-resolve-alias, but the stripped (ns …) form left
the alias table empty, so it landed in ns "ig".
bld-ns-prelude now emits (set-chez-ns! ns) plus chez-register-alias! for each
ns's :as aliases before that ns's forms, in both the normal and tree-shake emit
paths. The build-app fixture gains a :default multimethod and an aliased cross-ns
defmethod so buildsmoke covers both across all build modes.
set-optimize!/set-direct-link! are process-global flags in the back end, set then
reset around the emit. A strict-form build error (failing forms error the build by
design) skipped the reset, leaving the compiler in optimize/direct-link mode for any
later in-process caller. dynamic-wind guarantees the revert. Behaviour unchanged on
the success path; both --tree-shake and --opt --direct-link build + run identically.
Tree-shaking was split across emit-image.ss (the dce-* helpers + record producer)
and build.ss (bld-shake-all + the manifest splice), with the DCE record accessed by
raw (vector-ref r 0..3) in ~10 places and the manifest splice/drop driven by
substring-matching (load "…prelude.ss").
- New host/chez/dce.ss owns the whole DCE concern: a named record API
(dce-rec/-keep?/-fqn/-refs/-str — no more positional vector indexing), the ref
extraction + ref-set constants, dce-blob-records, and dce-shake decomposed into
dce-build-graph / dce-reachable / dce-bail-scan / dce-partition (was one 50-line
bld-shake-all doing five jobs with shared mutable state).
- emit-image.ss keeps only ei-emit-ns-records (it drives the ei-* compiler) and uses
the dce-rec constructor.
- The runtime manifest is now tagged ('prelude/'image/'compile-eval); bld-emit-runtime
dispatches on the tag instead of substring-matching file paths, so the core-splice
and compiler-drop can't silently break on a rename/reorder.
Behaviour-preserving (runtime .ss, no re-mint): build-app shakes identically
(56/460, 8.12MB), make test green, make shakesmoke green (4 git-lib apps
byte-identical, same sizes).
When --tree-shake keeps everything because reachable code resolves vars at runtime,
list the offending def -> bail-ref pairs (up to 6) instead of just saying it
skipped. Makes it actionable: e.g. ring-app shows
clojure.tools.logging/call-str -> ns-resolve and selmer.filters/generate-json ->
resolve, so you know which library (not your code) blocks shaking.
--tree-shake now shakes the clojure.core/stdlib prelude in the same reachability
graph as the app + libraries — only core fns actually reached from -main ship.
dce-blob-records reads prelude.ss with Chez `read`, unwraps each
(guard ... (def-var! "ns" "name" V)) and builds the core->core call graph from the
(var-deref/jolt-var "ns" "name") refs in V — the real emitted edges, no
re-analysis. bld-shake-all merges core + app records into one BFS; roots are -main,
side-effecting forms, and the clojure.core fns the runtime .ss shims reference by
name (enumerated in dce-runtime-core-roots). The shaken core is spliced where the
prelude.ss blob was, in original (tier) order, so load-time deps are preserved.
Bail (reachable runtime resolve) keeps the prelude whole.
Soundness follows Stalin's rule (any reference, value or call, keeps a def live):
dce-collect-refs counts :var and :the-var; non-def registration forms are always
kept (covers protocol/multimethod dispatch). Validated by make shakesmoke: the four
deps.edn git-lib apps build byte-identical output shaken vs not.
Wins (binary): build-app 9.84MB -> 8.12MB (dropped 403/457 core defs); malli-app
10.0MB -> 8.1MB; markdown 9.9 -> 8.3; commonmark 9.8 -> 8.1 — all output-identical.
build-smoke asserts an unused core fn (group-by) is dropped; full make test green.
An AOT-compiled app only needs the analyzer/back end at runtime to compile from
source — eval / load-string / load-file. Macros are expanded at build time and a
require of a baked namespace no-ops, so a closed app that never compiles at runtime
carries the compiler image (~0.8MB) as dead weight.
Under --tree-shake, when reachability is trustworthy (no bail) and no reachable code
references eval/load-string/load-file/load-reader/load, omit host/chez/seed/image.ss
+ compile-eval.ss from the runtime manifest. bld-tree-shake returns the flag
alongside the shaken forms; bld-emit-runtime filters the manifest.
Measured: build-app 9.84MB -> 9.05MB, still runs. Safety verified: an app that evals
keeps the compiler (eval is a bail + compile ref) and eval works at runtime.
build-smoke asserts the compiler is gone in the no-eval app; full make test green.
`jolt build --tree-shake` (or deps.edn :jolt/build {:tree-shake true}) does
reachability DCE over the re-emitted app + library namespaces: keep -main, every
side-effecting (non-def) top-level form, and every def reachable from those; drop
the rest. A macro (expanded at AOT, never called at runtime) is prunable too.
Sound: bails (keeps everything) if REACHABLE code resolves vars by name at runtime
(eval/resolve/ns-resolve/requiring-resolve/find-var/intern/load-string/...), which a
static call graph can't follow. Unreached eval-using library code is simply shaken
away and never triggers the bail. clojure.core and the compiler image stay baked
(prelude + image blobs), so only re-emitted namespaces are shaken for now.
The reachability machinery is in emit-image.ss (records: keep?/fqn/refs/str via
reduce-ir-children) + build.ss (BFS + bail check). build-smoke covers it (drops the
unreachable `twice` macro, output unchanged). Opt-in; default builds are untouched.
full make test green.
Scope note: this shakes the re-emitted app/lib code only. Measurement shows jolt's
compiled code is ~5.8MB of a ~9.8MB binary, dominated by the clojure.core prelude
(~1.5-2MB) and the compiler image (~0.8MB) — both baked blobs this pass doesn't
touch. Those (shake-core, drop-compiler-when-no-eval) are the larger footprint wins,
filed as follow-ups.
Release builds can legitimately want runtime dynamism (redefinition, eval,
load-string), so closed-world direct-linking shouldn't be forced on them. Gate it
behind an explicit --direct-link flag (or deps.edn :jolt/build {:direct-link
true}); off by default in every mode, including release and --opt.
build-binary takes an explicit direct-link? arg instead of deriving it from the
mode. build-smoke now covers the --direct-link path and asserts the cross-ns call
actually lowers to a jv$ binding; default release stays dynamically linked.
A release/optimized `jolt build` is a closed world: every app def is final, so
an app->app call can bind to the def's Scheme binding directly instead of going
through (jolt-invoke (var-deref ns name)).
The emitter gains a direct-link mode (off for the seed mint, runtime -e/repl, and
dev builds). With it on, a top-level app def also emits a binding jv$<ns>$<name>
that def-var! aliases; an app->app call or value-ref to a name already emitted in
the unit lowers to that binding, skipping both the var-table lookup and the
generic IFn dispatch. ^:dynamic/^:redef defs and nested defs (a defonce's inner
def) opt out and stay indirect. Off direct-link mode, emit-top-form is exactly
emit, so the seed and runtime eval are byte-unchanged (selfhost holds).
build.ss turns it on for release + optimized; the defined-set accumulates across
the dependency-ordered namespaces so a dep's defs are linkable by the time the
entry that calls them is emitted. App->core calls stay indirect for now (core is
the baked seed); that's a later stage.
~1.74x on a hot cross-namespace call loop (26.5s -> 15.2s).
A built binary dropped its deps.edn :jolt/native declarations and its
resource roots, so an FFI+resources app (ring-app) failed at runtime:
sockets/sqlite gave 'no entry for socket' and io/resource returned nil.
The buildsmoke fixture is pure compute, so neither path was exercised.
The launcher now loads required + :process native libs before the app's
top-level forms (a library's defcfn resolves its foreign-procedure symbols
at top-level eval during startup, so the libs must be loaded first);
optional libs load in the scheme-start launcher, where a missing lib is
caught rather than aborting the heap build.
deps.edn :jolt/build {:embed [dirs]} bakes those dirs' files into the heap
(register-embedded-resource! at heap build), so io/resource serves them with
no files on disk. Non-embedded resources resolve at runtime against JOLT_PWD,
and io/file reads (e.g. config.edn) stay external.
build-binary now takes the encoded natives, embed dirs, and project paths
from cmd-build; deps/resolve-project surfaces them. Buildsmoke fixture grows
an embedded resource + a :process native to cover both paths.
ei-emit-ns (emit-image) and bld-emit-ns (build) were near-verbatim copies that had
drifted: the minter guard-wraps and skips failing forms, the build is strict, and
since the passes were wired the build also runs run-passes. Fold both into
ei-emit-ns* with optimize?/guard? flags; ei-emit-ns and bld-emit-ns become one-line
callers. Output is byte-identical (selfhost fixpoint and build smoke stay green).
- take-last / drop-last return seqs, not vectors: take-last wraps in seq; drop-last
is the JVM (map (fn [x _] x) coll (drop n coll)) form (lazy, () when empty).
- cycle is lazy ((lazy-seq (concat coll (cycle coll)))) so it no longer counts its
argument and terminates on a lazy/infinite input.
- fold's foldable-call catch uses :default, matching the rest of jolt-core and
also catching a raw host condition from a folding primitive.
- alts! rejects non-channel ports with a clear error (put specs / :default are
unsupported) instead of crashing inside ac-poll!.
- Misc: drop the unreachable second getCause clause; jolt-nth on a string raises
'nth "index out of bounds" like the vector branch; name the inline fixpoint cap;
bld-sh-capture rejoins lines with newlines; clarify a couple of comments.
The fold/inline/types passes and the jolt.passes façade were baked into neither
seed half and never invoked: compile-eval and build went analyze -> emit directly,
and `jolt build --opt` flipped an optimize flag that nothing consumed.
- Compile the passes into the image (emit-image manifest): fold, inline, types,
then the jolt.passes façade, after jolt.ir.
- compile-eval and build.ss now run jolt.passes/run-passes between analyze and
emit. Off the direct-link path it is a pure const-fold; `jolt build --opt`
turns on inline + flatten + scalar-replace + type inference (it sets
hc-optimize?, which inline-enabled? reads).
- The seed minter (emit-image) stays analyze -> emit, so the seed is built
un-optimized and the self-host fixpoint is unaffected.
build-smoke already exercised --opt; it now actually optimizes and still matches
the release binary's output. Corpus floor and the fixpoint are green.
The apt chezscheme package ships petite+scheme only — no kernel dev files — so
the standalone-binary gate skipped on CI, leaving the whole jolt build pipeline
and the --opt inference passes uncovered on Linux. Build Chez v10.4.1 from
source (cached) to get libkernel.a + scheme.h, install the libs the kernel links
against, and set the Linux link flags. buildsmoke now runs for real in CI.
Wire the optimization gate to build mode. inline-enabled? (which gates the
inference + flatten-lets + scalar-replace passes in jolt.passes/run-passes) was
hardwired off, so those passes had never run on Chez at all. host-contract now
exposes a settable hc-optimize? flag; `jolt build --opt` flips it on during app
emission.
Kept off for the default release build for now: the passes are sound by design
(RFC 0005/0006) but unexercised on Chez, so release stays on the proven
var-deref codegen until they're validated against the corpus. --opt is the
opt-in fast path. buildsmoke checks both modes produce the same result.
This does not yet deliver direct call binding — the backend has no direct-link
emission path (every :var call still routes through jolt-invoke/var-deref) and
the inline-ir host stash is still a stub. Those are the remaining stage-4 levers.
Restores the standalone-binary capability the Janet host had. `bin/joltc build
-m NS -o OUT` AOT-compiles an app into a single self-contained executable — the
whole runtime, clojure.core, stdlib and compiler embedded, no Chez install or
jolt source needed at runtime.
Pipeline (host/chez/build.ss, host primitive jolt.host/build-binary driven by
jolt.main's build command): resolve deps, load the entry namespace recording the
app namespaces in dependency order, re-emit each to Scheme, textually inline the
cli.ss runtime load sequence into one flat source + the app + a launcher, then
compile-file -> make-boot-file -> embed the boot as C bytes -> cc-link against
libkernel.a.
Two non-obvious bits: the compile pass runs in a fresh Chez, not the loaded
runtime (regex.ss shadows top-level `error`, which otherwise bakes a broken
reference into the boot); and the launcher installs scheme-start rather than
running -main at top level, since boot top-level forms execute during heap build
before argv is set, so args only reach -main through scheme-start.
Loader: a require of an in-memory namespace with no source file now no-ops, so
AOT'd app namespaces satisfy require in a built binary.
Mode flags (--opt/--dev, default release) are plumbed; the optimization passes
they gate come in a later stage. RFC 0007 has the design. Gated by `make
buildsmoke`.
