diff --git a/lldb/include/lldb/Expression/ExpressionTypeSystemHelper.h b/lldb/include/lldb/Expression/ExpressionTypeSystemHelper.h
--- a/lldb/include/lldb/Expression/ExpressionTypeSystemHelper.h
+++ b/lldb/include/lldb/Expression/ExpressionTypeSystemHelper.h
@@ -29,6 +29,7 @@
     eKindClangHelper,
     eKindSwiftHelper,
     eKindGoHelper,
+    eKindMojoHelper,
     kNumKinds
   };
 
diff --git a/lldb/include/lldb/Expression/ExpressionVariable.h b/lldb/include/lldb/Expression/ExpressionVariable.h
--- a/lldb/include/lldb/Expression/ExpressionVariable.h
+++ b/lldb/include/lldb/Expression/ExpressionVariable.h
@@ -25,7 +25,7 @@
     : public std::enable_shared_from_this<ExpressionVariable> {
 public:
   // See TypeSystem.h for how to add subclasses to this.
-  enum LLVMCastKind { eKindClang, eKindSwift, eKindGo, kNumKinds };
+  enum LLVMCastKind { eKindClang, eKindSwift, eKindGo, eKindMojo, kNumKinds };
 
   LLVMCastKind getKind() const { return m_kind; }
 
@@ -203,7 +203,7 @@
 class PersistentExpressionState : public ExpressionVariableList {
 public:
   // See TypeSystem.h for how to add subclasses to this.
-  enum LLVMCastKind { eKindClang, eKindSwift, eKindGo, kNumKinds };
+  enum LLVMCastKind { eKindClang, eKindSwift, eKindGo, eKindMojo, kNumKinds };
 
   LLVMCastKind getKind() const { return m_kind; }
 
diff --git a/lldb/include/lldb/Expression/REPL.h b/lldb/include/lldb/Expression/REPL.h
--- a/lldb/include/lldb/Expression/REPL.h
+++ b/lldb/include/lldb/Expression/REPL.h
@@ -21,7 +21,7 @@
 class REPL : public IOHandlerDelegate {
 public:
   // See TypeSystem.h for how to add subclasses to this.
-  enum LLVMCastKind { eKindClang, eKindSwift, eKindGo, kNumKinds };
+  enum LLVMCastKind { eKindClang, eKindSwift, eKindGo, eKindMojo, kNumKinds };
 
   LLVMCastKind getKind() const { return m_kind; }