Avoid implementing Debug for QueryConfig

compiler/rustc_query_impl/src/plumbing.rs

@@ -462,7 +462,7 @@ mod queries {
             use std::marker::PhantomData;
 
             $(
-                #[derive(Copy, Clone, Debug)]
+                #[derive(Copy, Clone)]
                 pub struct $name<'tcx> {
                     data: PhantomData<&'tcx ()>
                 }

compiler/rustc_query_system/src/dep_graph/mod.rs

@@ -88,6 +88,15 @@ fn dep_context(&self) -> &Self::DepContext {
     }
 }
 
+impl<T: HasDepContext, Q: Copy> HasDepContext for (T, Q) {
+    type DepKind = T::DepKind;
+    type DepContext = T::DepContext;
+
+    fn dep_context(&self) -> &Self::DepContext {
+        self.0.dep_context()
+    }
+}
+
 /// Describes the contents of the fingerprint generated by a given query.
 #[derive(Debug, PartialEq, Eq, Copy, Clone)]
 pub enum FingerprintStyle {

compiler/rustc_query_system/src/query/config.rs

@@ -14,7 +14,7 @@
 
 pub type TryLoadFromDisk<Qcx, V> = Option<fn(Qcx, SerializedDepNodeIndex) -> Option<V>>;
 
-pub trait QueryConfig<Qcx: QueryContext>: Copy + Debug {
+pub trait QueryConfig<Qcx: QueryContext>: Copy {
     fn name(self) -> &'static str;
 
     // `Key` and `Value` are `Copy` instead of `Clone` to ensure copying them stays cheap,

compiler/rustc_query_system/src/query/plumbing.rs

@@ -468,9 +468,9 @@ fn execute_job<Q, Qcx>(
 
             dep_graph.with_task(
                 dep_node,
-                qcx,
-                (key, query),
-                |qcx, (key, query)| query.compute(qcx, key),
+                (qcx, query),
+                key,
+                |(qcx, query), key| query.compute(qcx, key),
                 query.hash_result(),
             )
         });