code: function getCFunc(ident) {
    try {
      var func = globalScope['Module']['_' + ident]; // closure exported function
      if (!func) func = eval('_' + ident); // explicit lookup
    } catch(e) {
    }
    assert(func, 'Cannot call unknown function ' + ident + ' (perhaps LLVM optimizations or closure removed it?)');
    return func;
  }
docs: Returns the C function with a specified identifier (for C++, you need to do manual name mangling)