Fix embind exports with MODULARIZE=instance and AUTO_INIT#27414
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Fix embind exports with MODULARIZE=instance and AUTO_INIT#27414guybedford wants to merge 1 commit into
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I would hope that we don't need to do this (instead maybe we could make it an assertion if this function is called too late), and we can instread find a way to do the registration before startup. Otherwise we might be tempted to support other event handler beeing registered too late too. @brendandahl WDYT? |
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I've updated the approach so postCtor events can only be registered before startup. |
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With AUTO_INIT the embind AOT export snippet was appended after the top-level `await init()`, so its addOnPostCtor callback registered after onPostCtors had already fired, leaving the ES module exports undefined. Emit the snippet via a placeholder ahead of the init logic in the postamble instead, and assert against late addOnPostCtor registration. Fixes emscripten-core#27411
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This fixes embind ES module exports being
undefinedwhen using-sMODULARIZE=instance -sAUTO_INIT -sEMBIND_AOT, resolves #27411.With AUTO_INIT the module self-initializes via top-level
await init()in the postamble, but the embind AOT export snippet was appended after the postamble. ItsaddOnPostCtor(assignEmbindExports)therefore registered only afteronPostCtorshad already fired during init, so the export assignments never ran.Following review feedback, rather than supporting late registration, the snippet is now emitted via a
<<< EMBIND_AOT_EXPORTS >>>placeholder at the start of the MODULARIZE=instance postamble (same mechanism asEMBIND_AOT_INVOKERS), so registration always precedes initialization.addOnPostCtoradditionally asserts under ASSERTIONS that it is not called after ctors have run, rather than silently never firing.Adds
other.test_modularize_instance_auto_init_embindreusingmodularize_instance_embind.cpp, verified to fail before the fix and pass after; existing modularize=instance, ESM integration, dylink and codesize tests still pass (also manually verified WASM_ESM_INTEGRATION + AUTO_INIT + EMBIND_AOT under node 26).Made with AI assistance under my review