diff --git a/include/etl/type_def.h b/include/etl/type_def.h
index f09a689e5..6f0071bb1 100644
--- a/include/etl/type_def.h
+++ b/include/etl/type_def.h
@@ -238,14 +238,14 @@ namespace etl
         }
 
         //*********************************************************************
-        ETL_CONSTEXPR type_def& operator =(TValue rhs)
+        type_def& operator =(TValue rhs)
         {
             value = rhs;
             return *this;
         }
 
         //*********************************************************************
-        ETL_CONSTEXPR type_def& operator =(const type_def& rhs)
+        type_def& operator =(const type_def& rhs)
         {
           value = rhs.value;
           return *this;