#[cfg] //~ ERROR `cfg` is not followed by parentheses struct S1; #[cfg = 10] //~ ERROR `cfg` is not followed by parentheses struct S2; #[cfg()] //~ ERROR `cfg` predicate is not specified struct S3; #[cfg(a, b)] //~ ERROR multiple `cfg` predicates are specified struct S4; #[cfg("str")] //~ ERROR `cfg` predicate key cannot be a literal struct S5; #[cfg(a::b)] //~ ERROR `cfg` predicate key must be an identifier struct S6; #[cfg(a())] //~ ERROR invalid predicate `a` struct S7; #[cfg(a = 10)] //~ ERROR literal in `cfg` predicate value must be a string struct S8; #[cfg(a = b"hi")] //~ ERROR literal in `cfg` predicate value must be a string struct S9; macro_rules! generate_s10 { ($expr: expr) => { #[cfg(feature = $expr)] //~^ ERROR expected unsuffixed literal, found `concat!("nonexistent")` //~| ERROR expected unsuffixed literal, found `concat!("nonexistent")` struct S10; } } generate_s10!(concat!("nonexistent")); fn main() {}