warning: `repr` attribute must have a hint
  --> $DIR/issue-43988.rs:34:5
   |
LL |     #[repr]
   |     ^^^^^^^ needs a hint
   |
   = note: #[warn(bad_repr)] on by default
   = help: valid hints include `#[repr(C)]`, `#[repr(packed)]`, `#[repr(rust)]` and `#[repr(transparent)]`
   = note: for more information, visit <https://doc.rust-lang.org/reference/type-layout.html>

warning: `repr` attribute must have a hint
  --> $DIR/issue-43988.rs:46:14
   |
LL |     let _z = #[repr] 1;
   |              ^^^^^^^ needs a hint
   |
   = help: valid hints include `#[repr(C)]`, `#[repr(packed)]`, `#[repr(rust)]` and `#[repr(transparent)]`
   = note: for more information, visit <https://doc.rust-lang.org/reference/type-layout.html>

error[E0518]: attribute should be applied to function or closure
  --> $DIR/issue-43988.rs:15:5
   |
LL |     #[inline]
   |     ^^^^^^^^^
LL |     let _a = 4;
   |     ----------- not a function or closure

error[E0518]: attribute should be applied to function or closure
  --> $DIR/issue-43988.rs:20:5
   |
LL |     #[inline(XYZ)]
   |     ^^^^^^^^^^^^^^
LL |     let _b = 4;
   |     ----------- not a function or closure

error[E0517]: attribute should not be applied to a statement
  --> $DIR/issue-43988.rs:24:5
   |
LL |     #[repr(nothing)]
   |     ^^^^^^^^^^^^^^^^
LL |     let _x = 0;
   |     ----------- not a struct, enum or union

error[E0517]: attribute should not be applied to an expression
  --> $DIR/issue-43988.rs:28:5
   |
LL |       #[repr(something_not_real)]
   |       ^^^^^^^^^^^^^^^^^^^^^^^^^^^
LL | /     loop {
LL | |         ()
LL | |     };
   | |_____- not defining a struct, enum or union

error[E0517]: attribute should not be applied to a statement
  --> $DIR/issue-43988.rs:34:5
   |
LL |     #[repr]
   |     ^^^^^^^
LL |     let _y = "123";
   |     --------------- not a struct, enum or union

error[E0518]: attribute should be applied to function or closure
  --> $DIR/issue-43988.rs:42:5
   |
LL |     #[inline(ABC)]
   |     ^^^^^^^^^^^^^^
LL |     foo();
   |     ----- not a function or closure

error[E0517]: attribute should not be applied to an expression
  --> $DIR/issue-43988.rs:46:14
   |
LL |     let _z = #[repr] 1;
   |              ^^^^^^^ - not defining a struct, enum or union

error: aborting due to 7 previous errors

Some errors occurred: E0517, E0518.
For more information about an error, try `rustc --explain E0517`.