Isolate `CrateNum` creation to `TyCtxt` methods

1 files changed, 10 insertions, 0 deletions

diff --git a/compiler/rustc_middle/src/ty/context.rs b/compiler/rustc_middle/src/ty/context.rs
index d30a4ac6a9c..3832fecfee4 100644
--- a/compiler/rustc_middle/src/ty/context.rs
+++ b/compiler/rustc_middle/src/ty/context.rs
@@ -1261,6 +1261,16 @@ impl<'tcx> TyCtxt<'tcx> {
         feed
     }
 
+    pub fn create_crate_num(self, stable_crate_id: StableCrateId) -> Result<CrateNum, CrateNum> {
+        if let Some(&existing) = self.untracked().stable_crate_ids.read().get(&stable_crate_id) {
+            return Err(existing);
+        }
+
+        let num = CrateNum::new(self.untracked().stable_crate_ids.read().len());
+        self.untracked().stable_crate_ids.write().insert(stable_crate_id, num);
+        Ok(num)
+    }
+
     pub fn iter_local_def_id(self) -> impl Iterator<Item = LocalDefId> + 'tcx {
         // Create a dependency to the red node to be sure we re-execute this when the amount of
         // definitions change.