Make DefPathHash->DefId panic for if the mapping fails.

We only use this mapping for cases where we know that it must succeed.
Letting it panic otherwise makes it harder to use the API in unsupported
ways.

1 files changed, 3 insertions, 10 deletions

diff --git a/compiler/rustc_query_impl/src/on_disk_cache.rs b/compiler/rustc_query_impl/src/on_disk_cache.rs
index 82cc81ec4c3..f9456a6f2cd 100644
--- a/compiler/rustc_query_impl/src/on_disk_cache.rs
+++ b/compiler/rustc_query_impl/src/on_disk_cache.rs
@@ -361,7 +361,7 @@ impl<'sess> rustc_middle::ty::OnDiskCache<'sess> for OnDiskCache<'sess> {
         })
     }
 
-    fn def_path_hash_to_def_id(&self, tcx: TyCtxt<'tcx>, hash: DefPathHash) -> Option<DefId> {
+    fn def_path_hash_to_def_id(&self, tcx: TyCtxt<'tcx>, hash: DefPathHash) -> DefId {
         debug!("def_path_hash_to_def_id({:?})", hash);
 
         let stable_crate_id = hash.stable_crate_id();
@@ -369,9 +369,7 @@ impl<'sess> rustc_middle::ty::OnDiskCache<'sess> for OnDiskCache<'sess> {
         // If this is a DefPathHash from the local crate, we can look up the
         // DefId in the tcx's `Definitions`.
         if stable_crate_id == tcx.sess.local_stable_crate_id() {
-            tcx.definitions_untracked()
-                .local_def_path_hash_to_def_id(hash)
-                .map(LocalDefId::to_def_id)
+            tcx.definitions_untracked().local_def_path_hash_to_def_id(hash).to_def_id()
         } else {
             // If this is a DefPathHash from an upstream crate, let the CrateStore map
             // it to a DefId.
@@ -779,12 +777,7 @@ impl<'a, 'tcx> Decodable<CacheDecoder<'a, 'tcx>> for DefId {
         // If we get to this point, then all of the query inputs were green,
         // which means that the definition with this hash is guaranteed to
         // still exist in the current compilation session.
-        Ok(d.tcx()
-            .on_disk_cache
-            .as_ref()
-            .unwrap()
-            .def_path_hash_to_def_id(d.tcx(), def_path_hash)
-            .unwrap())
+        Ok(d.tcx().on_disk_cache.as_ref().unwrap().def_path_hash_to_def_id(d.tcx(), def_path_hash))
     }
 }