diff --git a/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ast2/AST2TemplateTests.java b/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ast2/AST2TemplateTests.java
index a522e97af8b..72942eda1db 100644
--- a/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ast2/AST2TemplateTests.java
+++ b/core/org.eclipse.cdt.core.tests/parser/org/eclipse/cdt/core/parser/tests/ast2/AST2TemplateTests.java
@@ -5006,6 +5006,7 @@ public class AST2TemplateTests extends AST2BaseTest {
 		}
 		code.append("int_<0> >::type tdef;");
 		IASTTranslationUnit tu= parse(code.toString(), ParserLanguage.CPP, true, true);
+		tu = validateCopy(tu);
 		assertEquals(1, tu.getDeclarations().length);
 	}
 }