Bugzilla

This patch (which applies on top of the other 3) creates the wasm alt-data stream and writes it to that alt-data output stream.  The patch doesn't implement reading wasm alt-data, though; it just ignores the alt-data and reads the unfiltered body as before.  IIUC, because deliverAltData is set to false, this should still Just Work, and for small wasm modules it does.

But for big wasm modules, the unfiltered body produces bytes that are neither the original response nor the serialized bytes.  A simple tester app that shows this is:
  https://lukewagner.github.io/test-streaming/
If you apply my patches and click "Compile Small" twice, it works both times.  But if you click "Compile Big" twice, it fails reliably the second and all future times until the cache is cleared.  (Note you need to wait for the "### Stored optimized encoding" printf() to know that the alt-data was written; this can take a while in debug builds.)

The "Print" buttons print the bytes of the fetch() as an ArrayBuffer.  For "Print Small", we see the same bytes before and after "Compile Small".  However, "Print Big" shows different bytes before and after.

So something weird is happening for large (~34mb) alt-data.  Any ideas?

This patch (which applies on top of the other 3) creates the wasm alt-data stream and writes it to that alt-data output stream.  The patch doesn't implement reading wasm alt-data, though; it just ignores the alt-data and reads the unfiltered body as before.  IIUC, because deliverAltData is set to false, this should still Just Work, and for small wasm modules it does.

But for big wasm modules, the unfiltered body produces bytes that are neither the original response nor the serialized bytes.  A simple tester app that shows this is: https://lukewagner.github.io/test-streaming/

If you apply my patches and click "Compile Small" twice, it works both times.  But if you click "Compile Big" twice, it fails reliably the second and all future times until the cache is cleared.  (Note you need to wait for the "### Stored optimized encoding" printf() to know that the alt-data was written; this can take a while in debug builds.)

The "Print" buttons print the bytes of the fetch() as an ArrayBuffer.  For "Print Small", we see the same bytes before and after "Compile Small".  However, "Print Big" shows different bytes before and after.

So something weird is happening for large (~34mb) alt-data.  Any ideas?