diff --git a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/semantics/TemplateArgumentDeduction.java b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/semantics/TemplateArgumentDeduction.java
index 5995218080a..c2f04f1572b 100644
--- a/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/semantics/TemplateArgumentDeduction.java
+++ b/core/org.eclipse.cdt.core/parser/org/eclipse/cdt/internal/core/dom/parser/cpp/semantics/TemplateArgumentDeduction.java
@@ -839,7 +839,8 @@ public class TemplateArgumentDeduction {
 		// Try to deduce from the original argument type, but if it fails, fall back to the simplified
 		// argument type.
 		return fromType(p.getTypeValue(), a.getOriginalTypeValue(), false, point)
-				|| fromType(p.getTypeValue(), a.getTypeValue(), false, point);
+				|| (a.getTypeValue() != a.getOriginalTypeValue()
+						&& fromType(p.getTypeValue(), a.getTypeValue(), false, point));
 	}
 
 	private boolean fromType(IType p, IType a, boolean allowCVQConversion, IASTNode point) throws DOMException {