diff --git a/string/public/nsAReadableString.h b/string/public/nsAReadableString.h
index e34715bbf929..c21b7f7ed56a 100644
--- a/string/public/nsAReadableString.h
+++ b/string/public/nsAReadableString.h
@@ -374,11 +374,7 @@ class basic_nsAReadableString
     sometimes will.
   */
 
-#ifdef NEED_CPP_TEMPLATE_CAST_TO_BASE
 #define NS_READABLE_CAST(CharT, expr)  (NS_STATIC_CAST(const basic_nsAReadableString<CharT>&, (expr)))
-#else
-#define NS_READABLE_CAST(CharT, expr)  (expr)
-#endif
 
 template <class CharT>
 inline
diff --git a/xpcom/ds/nsAReadableString.h b/xpcom/ds/nsAReadableString.h
index e34715bbf929..c21b7f7ed56a 100644
--- a/xpcom/ds/nsAReadableString.h
+++ b/xpcom/ds/nsAReadableString.h
@@ -374,11 +374,7 @@ class basic_nsAReadableString
     sometimes will.
   */
 
-#ifdef NEED_CPP_TEMPLATE_CAST_TO_BASE
 #define NS_READABLE_CAST(CharT, expr)  (NS_STATIC_CAST(const basic_nsAReadableString<CharT>&, (expr)))
-#else
-#define NS_READABLE_CAST(CharT, expr)  (expr)
-#endif
 
 template <class CharT>
 inline
diff --git a/xpcom/string/public/nsAReadableString.h b/xpcom/string/public/nsAReadableString.h
index e34715bbf929..c21b7f7ed56a 100644
--- a/xpcom/string/public/nsAReadableString.h
+++ b/xpcom/string/public/nsAReadableString.h
@@ -374,11 +374,7 @@ class basic_nsAReadableString
     sometimes will.
   */
 
-#ifdef NEED_CPP_TEMPLATE_CAST_TO_BASE
 #define NS_READABLE_CAST(CharT, expr)  (NS_STATIC_CAST(const basic_nsAReadableString<CharT>&, (expr)))
-#else
-#define NS_READABLE_CAST(CharT, expr)  (expr)
-#endif
 
 template <class CharT>
 inline