The self-hosting harnesses link the IR they lower through compileC. Most
hand-picked a subset of runtime feature flags, which lacked dynTier: a
sanitized build compiles exactly the listed runtime sources, so programs
with jsval operations failed to link scr_js_value.c's entry points, and
harnesses passing no flags at all failed in both lanes.
Every such site now spreads moduleLinkFeatures (tests/harness/
link-features.ts), which is executableLinkFeatures, the selection
compile() uses, so a runtime unit added later cannot drift out of the
harness builds. moduleUsesDynTier joins the IR facade's unit gates.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>