error[E0277]: the size for values of type `[i32]` cannot be known at compilation time
  --> $DIR/feature-gate-offset-of-slice.rs:17:5
   |
LL |     offset_of!(S, c);
   |     ^^^^^^^^^^^^^^^^ doesn't have a size known at compile-time
   |
   = help: the trait `Sized` is not implemented for `[i32]`
   = note: this error originates in the macro `offset_of` (in Nightly builds, run with -Z macro-backtrace for more info)

error[E0277]: the size for values of type `[i32]` cannot be known at compilation time
  --> $DIR/feature-gate-offset-of-slice.rs:21:5
   |
LL |     offset_of!(T, y);
   |     ^^^^^^^^^^^^^^^^ doesn't have a size known at compile-time
   |
   = help: within `S`, the trait `Sized` is not implemented for `[i32]`, which is required by `S: Sized`
note: required because it appears within the type `S`
  --> $DIR/feature-gate-offset-of-slice.rs:3:8
   |
LL | struct S {
   |        ^
   = note: this error originates in the macro `offset_of` (in Nightly builds, run with -Z macro-backtrace for more info)

error[E0277]: the size for values of type `[i32]` cannot be known at compilation time
  --> $DIR/feature-gate-offset-of-slice.rs:25:5
   |
LL |     offset_of!(Tup, 1);
   |     ^^^^^^^^^^^^^^^^^^ doesn't have a size known at compile-time
   |
   = help: the trait `Sized` is not implemented for `[i32]`
   = note: this error originates in the macro `offset_of` (in Nightly builds, run with -Z macro-backtrace for more info)

error: aborting due to 3 previous errors

For more information about this error, try `rustc --explain E0277`.