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Author: cjgillot

src/librustc_query_system/query/config.rs

@@ -20,6 +20,8 @@ use std::borrow::Cow;
 use std::fmt::Debug;
 use std::hash::Hash;
 
+// The parameter `CTX` is required in librustc: implementations may need to access the `'tcx`
+// lifetime in `CTX = TyCtxt<'tcx>`.
 pub trait QueryConfig<CTX> {
     const NAME: &'static str;
     const CATEGORY: ProfileCategory;