diff --git a/include/boost/preprocessor/expr_if.hpp b/include/boost/preprocessor/expr_if.hpp
index a86ae10..be893a0 100644
--- a/include/boost/preprocessor/expr_if.hpp
+++ b/include/boost/preprocessor/expr_if.hpp
@@ -29,7 +29,7 @@
   <li>BOOST_PP_IF()</li>
 </ul>
 */
-#define BOOST_PP_EXPR_IF(COND,EXPR) BOOST_PP_EXPR_IF_BOOL(BOOST_PP_BOOL(COND),EXPR) // original:  BOOST_PP_DETAIL_CAT2(BOOST_PP_EXPR_IF,BOOST_PP_BOOL(COND))(EXPR)
+#define BOOST_PP_EXPR_IF(COND,EXPR) BOOST_PP_EXPR_IF_BOOL(BOOST_PP_BOOL(COND),EXPR) /* original:  BOOST_PP_DETAIL_CAT2(BOOST_PP_EXPR_IF,BOOST_PP_BOOL(COND))(EXPR) */
 
 #define BOOST_PP_EXPR_IF_BOOL(COND,EXPR) BOOST_PP_EXPR_IF_BOOL_DELAY(COND,EXPR)
 #define BOOST_PP_EXPR_IF_BOOL_DELAY(COND,EXPR) BOOST_PP_EXPR_IF##COND(EXPR)
diff --git a/include/boost/preprocessor/if.hpp b/include/boost/preprocessor/if.hpp
index 3e7f296..6f90104 100644
--- a/include/boost/preprocessor/if.hpp
+++ b/include/boost/preprocessor/if.hpp
@@ -35,7 +35,7 @@
   <li><a href="../../test/preprocessor_test.cpp">preprocessor_test.cpp</a></li>
 </ul>
 */
-#define BOOST_PP_IF(COND,THEN,ELSE) BOOST_PP_IF_BOOL(BOOST_PP_BOOL(COND),THEN,ELSE) // original:  BOOST_PP_DETAIL_CAT2(BOOST_PP_IF,BOOST_PP_BOOL(COND))(ELSE,THEN)
+#define BOOST_PP_IF(COND,THEN,ELSE) BOOST_PP_IF_BOOL(BOOST_PP_BOOL(COND),THEN,ELSE) /* original:  BOOST_PP_DETAIL_CAT2(BOOST_PP_IF,BOOST_PP_BOOL(COND))(ELSE,THEN) */
 
 #define BOOST_PP_IF_BOOL(COND,THEN,ELSE) BOOST_PP_IF_BOOL_DELAY(COND,THEN,ELSE)
 #define BOOST_PP_IF_BOOL_DELAY(COND,THEN,ELSE) BOOST_PP_IF##COND(THEN,ELSE)
diff --git a/include/boost/preprocessor/logical/bool.hpp b/include/boost/preprocessor/logical/bool.hpp
index 5234f1b..ddde33a 100644
--- a/include/boost/preprocessor/logical/bool.hpp
+++ b/include/boost/preprocessor/logical/bool.hpp
@@ -22,7 +22,7 @@
 
 <p>For example, <code>BOOST_PP_BOOL(3)</code> expands to <code>1</code>.</p>
 */
-#define BOOST_PP_BOOL(X) BOOST_PP_BOOL_DELAY(X) // original:  BOOST_PP_DETAIL_CAT2(BOOST_PP_BOOL,X)
+#define BOOST_PP_BOOL(X) BOOST_PP_BOOL_DELAY(X) /* original:  BOOST_PP_DETAIL_CAT2(BOOST_PP_BOOL,X) */
 #define BOOST_PP_BOOL_DELAY(X) BOOST_PP_BOOL##X
 
 /* BOOL can be implemented in O(1) tokens using saturated ADD & SUB.
diff --git a/include/boost/preprocessor/repeat.hpp b/include/boost/preprocessor/repeat.hpp
index 175f8fd..dd286e0 100644
--- a/include/boost/preprocessor/repeat.hpp
+++ b/include/boost/preprocessor/repeat.hpp
@@ -95,7 +95,7 @@ are directly supported.</p>
 #define BOOST_PP_REPEAT_2(C,M,D) BOOST_PP_REPEAT_AUTO_REC2(BOOST_PP_DETAIL_CAT2(BOOST_PP_R2_,C),(M,D))
 #define BOOST_PP_REPEAT_3(C,M,D) BOOST_PP_REPEAT_AUTO_REC3(BOOST_PP_DETAIL_CAT2(BOOST_PP_R3_,C),(M,D))
 
-#if defined(__EDG_VERSION__) && (__EDG_VERSION__ <= 245) // unrolled repeats for EDG front end
+#if defined(__EDG_VERSION__) && (__EDG_VERSION__ <= 245) /* unrolled repeats for EDG front end */
 #include <boost/preprocessor/detail/repeat_edg.hpp>
 #else