1 error: lifetime parameter `'a` only used once
2 --> $DIR/issue-104440.rs:63:8
10 note: the lint level is defined here
11 --> $DIR/issue-104440.rs:2:9
13 LL | #![deny(single_use_lifetimes)]
14 | ^^^^^^^^^^^^^^^^^^^^
16 error: lifetime parameter `'a` only used once
17 --> $DIR/issue-104440.rs:38:30
19 LL | fn f<'b, 'c, $a: 'b, 'a: 'c>(t1: &$a(), t2: &'a ()) -> (&'b (), &'c ()) {
20 | ^^ this lifetime... -- ...is used only here
23 | ------ in this macro invocation
25 = note: this error originates in the macro `m` (in Nightly builds, run with -Z macro-backtrace for more info)
27 error: aborting due to 2 previous errors