error[E0124]: field `a` is already declared --> $DIR/fields-definition.rs:14:13 | LL | a: u8, | ----- `a` first declared here LL | $a: u8, | ^^^^^^ field already declared ... LL | legacy!(a); | ---------- in this macro invocation | = note: this error originates in the macro `legacy` (in Nightly builds, run with -Z macro-backtrace for more info) error: aborting due to 1 previous error For more information about this error, try `rustc --explain E0124`.