diff --git a/mozilla/xpcom/base/nscore.h b/mozilla/xpcom/base/nscore.h
index 8dfcea85688..d52b94ae5ec 100644
--- a/mozilla/xpcom/base/nscore.h
+++ b/mozilla/xpcom/base/nscore.h
@@ -154,15 +154,15 @@ typedef PRUint16 PRUnichar;
     Need to add an autoconf test for this.
   */
 
-  // under Metrowerks (Mac), we don't have autoconf yet
+  /* under Metrowerks (Mac), we don't have autoconf yet */
 #ifdef __MWERKS__
   #define HAVE_CPP_SPECIALIZATION
   #define HAVE_CPP_MODERN_SPECIALIZE_TEMPLATE_SYNTAX
 #endif
 
-  // under VC++ (Windows), we don't have autoconf yet
+  /* under VC++ (Windows), we don't have autoconf yet */
 #if defined(_MSC_VER) && (_MSC_VER>=1100)
-  // VC++ 5.0 and greater implement template specialization, 4.2 is unknown
+  /* VC++ 5.0 and greater implement template specialization, 4.2 is unknown */
   #define HAVE_CPP_SPECIALIZATION
   #define HAVE_CPP_MODERN_SPECIALIZE_TEMPLATE_SYNTAX
 #endif