error[E0060]: this function takes at least 1 parameter but 0 parameters were supplied
  --> $DIR/E0060.rs:16:14
   |
12 |     fn printf(_: *const u8, ...) -> u32;
   |     ------------------------------------ defined here
...
16 |     unsafe { printf(); }
   |              ^^^^^^^^ expected at least 1 parameter

error: aborting due to previous error

If you want more information on this error, try using "rustc --explain E0060"