Index: lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.cpp
===================================================================
--- lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.cpp
+++ lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.cpp
@@ -2002,6 +2002,8 @@
   ASTContext &ast = getASTContext();
   if (!decl_ctx)
     decl_ctx = ast.getTranslationUnitDecl();
+  assert(!decl_ctx->isRecord() &&
+         "Use AddMethodToCXXRecordType to add member functions to a record");
 
   const bool hasWrittenPrototype = true;
   const bool isConstexprSpecified = false;