unreachable code javascript

1// Warning: unreachable code after return statement (Firefox)
2
3/* The JavaScript warning "unreachable code after return statement" occurs when
4using an expression after a return statement, or when using a semicolon-less
5return statement but including an expression directly after. */
6
7function f() {
8  return 3 + 4; // Returns 7
9  console.log("Hey") // Not happening.
10}