src/runtime_assertions.js

/**
 * @license
 * Copyright 2019 The Emscripten Authors
 * SPDX-License-Identifier: MIT
 */

#if ASSERTIONS

// Endianness check
#if !SUPPORT_BIG_ENDIAN
(function() {
  var h16 = new Int16Array(1);
  var h8 = new Int8Array(h16.buffer);
  h16[0] = 0x6373;
  if (h8[0] !== 0x73 || h8[1] !== 0x63) throw 'Runtime error: expected the system to be little-endian! (Run with -s SUPPORT_BIG_ENDIAN=1 to bypass)';
})();
#endif

#endif // ASSERTIONS