error[E0025]: field `a` bound multiple times in the pattern
  --> $DIR/issue-15260.rs:8:9
   |
LL |         a: _,
   |         ---- first use of `a`
LL |         a: _
   |         ^^^^ multiple uses of `a` in pattern

error[E0025]: field `a` bound multiple times in the pattern
  --> $DIR/issue-15260.rs:14:9
   |
LL |         a,
   |         - first use of `a`
LL |         a: _
   |         ^^^^ multiple uses of `a` in pattern

error[E0025]: field `a` bound multiple times in the pattern
  --> $DIR/issue-15260.rs:20:9
   |
LL |         a,
   |         - first use of `a`
LL |         a: _,
   |         ^^^^ multiple uses of `a` in pattern

error[E0025]: field `a` bound multiple times in the pattern
  --> $DIR/issue-15260.rs:22:9
   |
LL |         a,
   |         - first use of `a`
...
LL |         a: x
   |         ^^^^ multiple uses of `a` in pattern

error: aborting due to 4 previous errors

For more information about this error, try `rustc --explain E0025`.