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jackh726 · web-flow · commit c9fbaa6a9f68 · 2021-04-28T15:51:54.000-04:00
diff --git a/compiler/rustc_middle/src/ty/flags.rs b/compiler/rustc_middle/src/ty/flags.rs
@@ -59,6 +59,9 @@ impl FlagComputation {
     {
         let mut computation = FlagComputation::new();
 
+        // In some cases, there are binders with variables that are unused (e.g., `for<'a> fn(u32)`).
+        // Set the flag to represent the `'a` in this example. Note that if there are late bound types
+        // or consts, this flag will also get set.
         if !value.bound_vars().is_empty() {
             computation.flags = computation.flags | TypeFlags::HAS_RE_LATE_BOUND;
         }

Original file line number	Diff line number	Diff line change
`@@ -59,6 +59,9 @@ impl FlagComputation {`
`59`	`59`	`{`
`60`	`60`	`let mut computation = FlagComputation::new();`
`61`	`61`
	`62`	+ // In some cases, there are binders with variables that are unused (e.g., `for<'a> fn(u32)`).
	`63`	+ // Set the flag to represent the `'a` in this example. Note that if there are late bound types
	`64`	`+ // or consts, this flag will also get set.`
`62`	`65`	`if !value.bound_vars().is_empty() {`
`63`	`66`	`computation.flags = computation.flags \| TypeFlags::HAS_RE_LATE_BOUND;`
`64`	`67`	`}`