error[E0277]: `dyn for<'a, 'b> Fn(&'a Foo<'b>) -> &'a Foo<'b>` cannot be shared between threads safely --> $DIR/rfc1623.rs:21:1 | LL | / static SOME_STRUCT: &SomeStruct = &SomeStruct { LL | | foo: &Foo { bools: &[false, true] }, LL | | bar: &Bar { bools: &[true, true] }, LL | | f: &id, LL | | LL | | }; | |__^ `dyn for<'a, 'b> Fn(&'a Foo<'b>) -> &'a Foo<'b>` cannot be shared between threads safely | = help: within `&SomeStruct`, the trait `Sync` is not implemented for `dyn for<'a, 'b> Fn(&'a Foo<'b>) -> &'a Foo<'b>` = note: required because it appears within the type `&dyn for<'a, 'b> Fn(&'a Foo<'b>) -> &'a Foo<'b>` = note: required because it appears within the type `SomeStruct` = note: required because it appears within the type `&SomeStruct` = note: shared static variables must have a type that implements `Sync` error: higher-ranked subtype error --> $DIR/rfc1623.rs:21:35 | LL | static SOME_STRUCT: &SomeStruct = &SomeStruct { | ___________________________________^ LL | | foo: &Foo { bools: &[false, true] }, LL | | bar: &Bar { bools: &[true, true] }, LL | | f: &id, LL | | LL | | }; | |_^ error: higher-ranked subtype error --> $DIR/rfc1623.rs:21:35 | LL | static SOME_STRUCT: &SomeStruct = &SomeStruct { | ___________________________________^ LL | | foo: &Foo { bools: &[false, true] }, LL | | bar: &Bar { bools: &[true, true] }, LL | | f: &id, LL | | LL | | }; | |_^ error: higher-ranked subtype error --> $DIR/rfc1623.rs:21:35 | LL | static SOME_STRUCT: &SomeStruct = &SomeStruct { | ___________________________________^ LL | | foo: &Foo { bools: &[false, true] }, LL | | bar: &Bar { bools: &[true, true] }, LL | | f: &id, LL | | LL | | }; | |_^ error: higher-ranked subtype error --> $DIR/rfc1623.rs:21:35 | LL | static SOME_STRUCT: &SomeStruct = &SomeStruct { | ___________________________________^ LL | | foo: &Foo { bools: &[false, true] }, LL | | bar: &Bar { bools: &[true, true] }, LL | | f: &id, LL | | LL | | }; | |_^ error: aborting due to 5 previous errors For more information about this error, try `rustc --explain E0277`.