diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index d1eb0ac54aa..c3a7845538d 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+Fri Mar  2 12:18:13 2001  Christopher Faylor <cgf@cygnus.com>
+
+	* cppinit.c (append_include_chain): Mark "after" include file name list
+	as a system directory.
+	* cpp.texi: Document new behavior.
+
 Fri Mar  2 11:59:43 CET 2001  Jan Hubicka  <jh@suse.cz>
 
 	* ifcvt.c (noce_operand_ok): Handle properly unarry operations.
diff --git a/gcc/cpp.texi b/gcc/cpp.texi
index 1c7b5a7cfcc..79efd480aff 100644
--- a/gcc/cpp.texi
+++ b/gcc/cpp.texi
@@ -3590,10 +3590,10 @@ before processing the regular input file.
 @item -idirafter @var{dir}
 @findex -idirafter
 @cindex second include path
-Add the directory @var{dir} to the second include path.  The directories
-on the second include path are searched when a header file is not found
-in any of the directories in the main include path (the one that
-@samp{-I} adds to).
+Add the directory @var{dir} to the second include path, marking it as a
+system directory.  The directories on the second include path are searched
+when a header file is not found in any of the directories in the main
+include path (the one that @samp{-I} adds to).
 
 @item -iprefix @var{prefix}
 @findex -iprefix
@@ -3603,9 +3603,10 @@ final @samp{/}.
 
 @item -iwithprefix @var{dir}
 @findex -iwithprefix
-Add a directory to the second include path.  The directory's name is
-made by concatenating @var{prefix} and @var{dir}, where @var{prefix} was
-specified previously with @samp{-iprefix}.
+Add a directory to the second include path, marking it as a system
+directory.  The directory's name is made by concatenating @var{prefix}
+and @var{dir}, where @var{prefix} was specified previously with
+@samp{-iprefix}.
 
 @item -isystem @var{dir}
 @findex -isystem
diff --git a/gcc/cppinit.c b/gcc/cppinit.c
index 0406e629040..61f72b4544e 100644
--- a/gcc/cppinit.c
+++ b/gcc/cppinit.c
@@ -237,7 +237,10 @@ append_include_chain (pfile, dir, path, cxx_aware)
   new->len = len;
   new->ino  = st.st_ino;
   new->dev  = st.st_dev;
-  if (path == SYSTEM)
+  /* Both systm and after include file lists should be treated as system
+     include files since these two lists are really just a concatenation
+     of one "system" list. */
+  if (path == SYSTEM || path == AFTER)
 #ifdef NO_IMPLICIT_EXTERN_C
     new->sysp = 1;
 #else