diff --git a/lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionParser.cpp b/lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionParser.cpp
index 2b00557d2e77b..0526e87de93e0 100644
--- a/lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionParser.cpp
+++ b/lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionParser.cpp
@@ -1298,6 +1298,10 @@ ClangExpressionParser::ParseInternal(DiagnosticManager &diagnostic_manager,
   m_compiler->setSema(nullptr);
 
   adapter->EndSourceFile();
+  // Creating persistent variables can trigger diagnostic emission.
+  // Make sure we reset the manager so we don't get asked to handle
+  // diagnostics after we finished parsing.
+  adapter->ResetManager();
 
   unsigned num_errors = adapter->getNumErrors();
 
@@ -1313,8 +1317,6 @@ ClangExpressionParser::ParseInternal(DiagnosticManager &diagnostic_manager,
     type_system_helper->CommitPersistentDecls();
   }
 
-  adapter->ResetManager();
-
   return num_errors;
 }