diff --git a/clang/include/clang/AST/Type.h b/clang/include/clang/AST/Type.h
--- a/clang/include/clang/AST/Type.h
+++ b/clang/include/clang/AST/Type.h
@@ -5071,8 +5071,10 @@
   static void Profile(llvm::FoldingSetNodeID &ID, TemplateName Template,
                       QualType Deduced, bool IsDependent) {
     Template.Profile(ID);
-    ID.AddPointer(Deduced.getAsOpaquePtr());
-    ID.AddBoolean(IsDependent);
+    QualType CanonicalType =
+        Deduced.isNull() ? Deduced : Deduced.getCanonicalType();
+    ID.AddPointer(CanonicalType.getAsOpaquePtr());
+    ID.AddBoolean(IsDependent || Template.isDependent());
   }
 
   static bool classof(const Type *T) {
diff --git a/clang/lib/AST/ASTContext.cpp b/clang/lib/AST/ASTContext.cpp
--- a/clang/lib/AST/ASTContext.cpp
+++ b/clang/lib/AST/ASTContext.cpp
@@ -5644,6 +5644,9 @@
 
   auto *DTST = new (*this, TypeAlignment)
       DeducedTemplateSpecializationType(Template, DeducedType, IsDependent);
+  llvm::FoldingSetNodeID TempID;
+  DTST->Profile(TempID);
+  assert(ID == TempID && "ID does not match");
   Types.push_back(DTST);
   if (InsertPos)
     DeducedTemplateSpecializationTypes.InsertNode(DTST, InsertPos);