---

yaml
---
r: 348991
b: refs/heads/master
c: 97339a6
h: refs/heads/master
i:
  348989: 01f6b6b
  348987: 7330db1
  348983: cf5430b
  348975: 5653a03
  348959: 4b99b7c
  348927: 6164303

Author: theblixguy

[refs]

@@ -1,5 +1,5 @@
 ---
-refs/heads/master: 9e89d56c57b4bdb63efc6dbc67942fcd63320f27
+refs/heads/master: 97339a6aceee09d417f17c31dc272a6475c0ff63
 refs/heads/master-next: 203b3026584ecad859eb328b2e12490099409cd5
 refs/tags/osx-passed: b6b74147ef8a386f532cf9357a1bde006e552c54
 refs/tags/swift-2.2-SNAPSHOT-2015-12-01-a: 6bb18e013c2284f2b45f5f84f2df2887dc0f7dea

trunk/lib/AST/ASTMangler.cpp

@@ -2649,10 +2649,17 @@ void ASTMangler::appendDependentProtocolConformance(
 void ASTMangler::appendConcreteProtocolConformance(
                                       const ProtocolConformance *conformance) {
   auto module = conformance->getDeclContext()->getParentModule();
-  if (!CurGenericSignature && conformance->getGenericSignature()) {
-    CurGenericSignature =
-        conformance->getGenericSignature()->getCanonicalSignature();
-  }
+
+  // It's possible that we might not have a generic signature here to get
+  // the conformance access path (for example, when mangling types for
+  // debugger). In that case, we can use the generic signature of the
+  // conformance (if it's present).
+  auto conformanceSig = conformance->getGenericSignature();
+  auto shouldUseConformanceSig = !CurGenericSignature && conformanceSig;
+  llvm::SaveAndRestore<CanGenericSignature> savedSignature(
+      CurGenericSignature, shouldUseConformanceSig
+                               ? conformanceSig->getCanonicalSignature()
+                               : CurGenericSignature);
 
   // Conforming type.
   Type conformingType = conformance->getType();