fix(runtime): #4876 keep js_promise_report_unhandled_rejections alive through auto-optimize LTO#4883
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… through auto-optimize LTO Codegen emits an unconditional call to js_promise_report_unhandled_rejections in the generated _main (the program-end unhandled-rejection hook from the #4838/#4852 work), but the runtime symbol was being dropped by the auto-optimize whole-program-bitcode internalize+dead-strip pass. The fn is #[no_mangle] pub extern "C" and reachable only from generated .o, so without a #[used] anchor LTO internalized and stripped it — every native link (aarch64-apple-{darwin,ios,tvos}, x86_64-unknown-linux-gnu) failed with 'undefined symbol: js_promise_report_unhandled_rejections'. Android linked because it doesn't go through the same auto-optimize bitcode path. Fix: add a #[used] KEEP anchor in promise/then.rs, matching the existing keepalive pattern in error.rs and promise/combinators.rs.
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) The auto-optimize runtime/stdlib rebuild caches its output in a `target/perry-auto-{hash}` dir keyed only on (features, panic_mode, target, wasm-host) — not on the compiler version. The object cache is already version-invalidated (build_cache.rs misses on `perry_version != CARGO_PKG_VERSION`), so the two caches disagree across a compiler upgrade on a persistent build host: - object cache rebuilds program objects with the new codegen, which emits calls to newly-added runtime entrypoints; while - the version-blind perry-auto dir hands back a stale `libperry_runtime.a` from the previous compiler that predates those symbols. Result: the final link fails with "undefined symbol" for exactly the entrypoints added since the cached runtime was built (and only those — older entrypoints resolve fine), e.g. `js_promise_run_promise_jobs`, `js_register_closure_strict_function`, `js_iterator_result_validate`, `js_promise_report_unhandled_rejections`, `js_mark_entry_module_esm`. This is why #4883's per-symbol `#[used]` anchor didn't help: the symbol isn't being stripped from a fresh build, it's absent from a stale cached one. Add `CARGO_PKG_VERSION` to the cache key so a compiler upgrade forces a matching runtime rebuild, mirroring the object cache. Co-authored-by: Ralph Küpper <ralph@skelpo.com>
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Fixes #4876.
Problem
Starting with v0.5.1151, every native link fails with:
Codegen emits an unconditional call to
js_promise_report_unhandled_rejectionsin the generated_main(the program-end unhandled-rejection hook added by the #4838/#4852 readable-unhandled-rejection work). The runtime defines the symbol (#[no_mangle] pub extern "C"inpromise/then.rs), but the auto-optimize whole-program-bitcode internalize + dead-strip pass drops it: the function is reachable only from generated.o, and without a#[used]anchor LTO internalizes then strips it.Affected:
aarch64-apple-{darwin,ios,tvos},x86_64-unknown-linux-gnu. Android linked because it doesn't go through the same auto-optimize bitcode path.Fix
Add a
#[used] static KEEP_PROMISE_REPORT_UNHANDLED_REJECTIONSanchor incrates/perry-runtime/src/promise/then.rs, matching the established keepalive pattern for codegen-only FFIs inerror.rsandpromise/combinators.rs.Validation
Built perry + runtime/stdlib, cleared
.perry-cache, compiled a minimal program with an unhandledPromise.reject. The auto-optimize path (rebuilds runtime+stdlib with LTO) now links cleanly:Before this fix the same compile failed at link with the undefined symbol.