error[E0138]: multiple 'start' functions
  --> $DIR/E0138.rs:17:1
   |
LL | fn foo(argc: isize, argv: *const *const u8) -> isize { 0 }
   | ---------------------------------------------------------- previous `start` function here
...
LL | fn f(argc: isize, argv: *const *const u8) -> isize { 0 }
   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ multiple `start` functions

error: aborting due to previous error

For more information about this error, try `rustc --explain E0138`.