rtrace

A tiny utility that records allocations, retains, releases and frees performed by the runtime and emits an error if something is off. Also checks for leaks.

Instructions

Compile your module that uses the full or half runtime with -use ASC_RTRACE=1 and include an instance of this module as the import named rtrace.

var rtr = rtrace(e => {
  // handle error
});

WebAssembly.instantiate(..., { rtrace: rtr, ... });
...

if (rtr.active) {
  let leakCount = rtr.leakCount;
  if (leakCount) {
    // handle error
  }
}

Note that references retained in globals which are not cleared before execution concludes appear as leaks, including their inner members. A TypedArray would leak itself and its backing ArrayBuffer in this case for example. This is perfectly normal and clearing all globals avoids this.