| error: unused variable: `var` | 
 |   --> $DIR/issue-117284-arg-in-macro.rs:4:13 | 
 |    | | 
 | LL |         let $var = $struct.$var; | 
 |    |             ^^^^ | 
 | ... | 
 | LL |     make_var!(s, var); | 
 |    |     ----------------- in this macro invocation | 
 |    | | 
 | help: `var` is captured in macro and introduced a unused variable | 
 |   --> $DIR/issue-117284-arg-in-macro.rs:4:13 | 
 |    | | 
 | LL |         let $var = $struct.$var; | 
 |    |             ^^^^ | 
 | ... | 
 | LL |     make_var!(s, var); | 
 |    |     ----------------- in this macro invocation | 
 | note: the lint level is defined here | 
 |   --> $DIR/issue-117284-arg-in-macro.rs:1:9 | 
 |    | | 
 | LL | #![deny(unused_variables)] | 
 |    |         ^^^^^^^^^^^^^^^^ | 
 |    = note: this error originates in the macro `make_var` (in Nightly builds, run with -Z macro-backtrace for more info) | 
 |  | 
 | error: unused variable: `a` | 
 |   --> $DIR/issue-117284-arg-in-macro.rs:16:9 | 
 |    | | 
 | LL |     let a = 1; | 
 |    |         ^ help: if this is intentional, prefix it with an underscore: `_a` | 
 |  | 
 | error: aborting due to 2 previous errors | 
 |  |