diff --git a/tests/auto/cplusplus/ast/tst_ast.cpp b/tests/auto/cplusplus/ast/tst_ast.cpp
index c67cd538696..f97b47a82e7 100644
--- a/tests/auto/cplusplus/ast/tst_ast.cpp
+++ b/tests/auto/cplusplus/ast/tst_ast.cpp
@@ -94,6 +94,7 @@ public:
 
 private slots:
     void initTestCase();
+    void cleanup();
 
     // line/column positions
     void line_and_column_1();
@@ -1687,6 +1688,11 @@ void tst_AST::initTestCase()
     control.setDiagnosticClient(&diag);
 }
 
+void tst_AST::cleanup()
+{
+    diag.errorCount = 0;
+}
+
 void tst_AST::line_and_column_1()
 {
     QSharedPointer<TranslationUnit> unit(parseDeclaration("\n"