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When switching to Kotlin 2.10-Beta2 from 2.10-Beta1 got error while building production. (More in thread...)

```Fatal: Internal GlobalTypeRewriter build error: Heap type has an invalid supertype at index 6

Execution failed for task ':app:compileProductionExecutableKotlinWasmJsOptimize'.
&gt; Process 'command '/home/user/.gradle/binaryen/binaryen-version_119/bin/wasm-opt'' finished with non-zero exit value 1```

Development build is fine while building and at runtime.

If it is not known issue, please advice where to dig to be able to narrow project to make reproducible.

Looks like a but in <https://github.com/WebAssembly/binaryen|binaryen> we using for optimization in production.
Could you please file an issue <https://github.com/WebAssembly/binaryen/issues|there>? (And share it here)

<https://github.com/WebAssembly/binaryen/issues/7015>

<@UFCJF8B9A> I’m wondering if could share the original kotlin project as well.

I'll try to extract problem source then. Now for wasm repro it can have some private code, sources of which i need to remove.

<@U0BMF6PDJ> there is one comment in issue that i've created. I don't know what they are talking about (i'm not working with wasm directly), but i think it gives you some info that helps to make generated code Kotlin-&gt;Wasm more optimized/minimized. Here is the link to this comment: <https://github.com/WebAssembly/binaryen/issues/7015#issuecomment-2420308261|https://github.com/WebAssembly/binaryen/issues/7015#issuecomment-2420308261>

<@UFCJF8B9A> I guess you have `suspend fun main` in the code, could you please try the same without it?

<@U0BMF6PDJ> by the way, i noticed when Gradle task compileProductionExecutableKotlinWasmJsOptimize calling wasm-opt command there are several O3 and Oz options passed. Is it expected?
The command for reference:
```/home/user/.gradle/binaryen/binaryen-version_119/bin/wasm-opt --enable-gc --enable-reference-types --enable-exception-handling --enable-bulk-memory --enable-nontrapping-float-to-int --closed-world --inline-functions-with-loops --traps-never-happen --fast-math --type-ssa -O3 -O3 --gufa -O3 --type-merging -O3 -Oz in.wasm -o out.wasm```

<@UFCJF8B9A> yes, it’s intended, it’s a way to setup optimization pipeline in binaryen, <https://github.com/WebAssembly/binaryen/wiki/GC-Optimization-Guidebook#multiple-optimization-passes|here is a reference>.

<@UFCJF8B9A> am I right that in the original code your `suspend fun main`  had `@JsExport` annotation? If so, I’m wondering why.

No. I have no annotations on 'suspend fun main()'