error[E0617]: can't pass `f32` to variadic function
  --> $DIR/E0617.rs:19:36
   |
19 |         printf(::std::ptr::null(), 0f32);
   |                                    ^^^^ help: cast the value to `c_double`: `0f32 as c_double`

error[E0617]: can't pass `i8` to variadic function
  --> $DIR/E0617.rs:22:36
   |
22 |         printf(::std::ptr::null(), 0i8);
   |                                    ^^^ help: cast the value to `c_int`: `0i8 as c_int`

error[E0617]: can't pass `i16` to variadic function
  --> $DIR/E0617.rs:25:36
   |
25 |         printf(::std::ptr::null(), 0i16);
   |                                    ^^^^ help: cast the value to `c_int`: `0i16 as c_int`

error[E0617]: can't pass `u8` to variadic function
  --> $DIR/E0617.rs:28:36
   |
28 |         printf(::std::ptr::null(), 0u8);
   |                                    ^^^ help: cast the value to `c_uint`: `0u8 as c_uint`

error[E0617]: can't pass `u16` to variadic function
  --> $DIR/E0617.rs:31:36
   |
31 |         printf(::std::ptr::null(), 0u16);
   |                                    ^^^^ help: cast the value to `c_uint`: `0u16 as c_uint`

error[E0617]: can't pass `unsafe extern "C" fn(*const i8, ...) {printf}` to variadic function
  --> $DIR/E0617.rs:34:36
   |
34 |         printf(::std::ptr::null(), printf);
   |                                    ^^^^^^
help: cast the value to `unsafe extern "C" fn(*const i8, ...)`
   |
34 |         printf(::std::ptr::null(), printf as unsafe extern "C" fn(*const i8, ...));
   |                                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

error: aborting due to 6 previous errors

If you want more information on this error, try using "rustc --explain E0617"