error: the meaning of the `pat` fragment specifier is changing in Rust 2021, which may affect this macro --> $DIR/macro-or-patterns-back-compat.rs:10:21 | LL | macro_rules! foo { ($x:pat | $y:pat) => {} } | ^^^^^^ help: use pat_param to preserve semantics: `$x:pat_param` | note: the lint level is defined here --> $DIR/macro-or-patterns-back-compat.rs:4:9 | LL | #![deny(rust_2021_incompatible_or_patterns)] | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021! = note: for more information, see error: the meaning of the `pat` fragment specifier is changing in Rust 2021, which may affect this macro --> $DIR/macro-or-patterns-back-compat.rs:13:23 | LL | macro_rules! bar { ($($x:pat)+ | $($y:pat)+) => {} } | ^^^^^^ help: use pat_param to preserve semantics: `$x:pat_param` | = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021! = note: for more information, see error: the meaning of the `pat` fragment specifier is changing in Rust 2021, which may affect this macro --> $DIR/macro-or-patterns-back-compat.rs:19:21 | LL | macro_rules! ogg { ($x:pat | $y:pat_param) => {} } | ^^^^^^ help: use pat_param to preserve semantics: `$x:pat_param` | = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021! = note: for more information, see error: the meaning of the `pat` fragment specifier is changing in Rust 2021, which may affect this macro --> $DIR/macro-or-patterns-back-compat.rs:23:26 | LL | ( $expr:expr , $( $( $pat:pat )|+ => $expr_arm:expr ),+ ) => { | ^^^^^^^^ help: use pat_param to preserve semantics: `$pat:pat_param` | = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021! = note: for more information, see error: aborting due to 4 previous errors