third_party/wasm-api/example/trap.wat - v8/v8 - Git at Google

 (module
   (func $callback (import "" "callback") (result i32))
   (func (export "callback") (result i32) (call $callback))
   (func (export "unreachable") (result i32) (unreachable) (i32.const 1))
 )
	(module
	(func $callback (import "" "callback") (result i32))
	(func (export "callback") (result i32) (call $callback))
	(func (export "unreachable") (result i32) (unreachable) (i32.const 1))
	)