diff --git a/ChangeLog b/ChangeLog
index 72898640..fe8d07f2 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -6,6 +6,7 @@
 	Using the -C +file option is a much better way for user
 	modifications.
 	* doc/avrdude.texi: (Dito.)
+	* avrdude.conf.in: Add a warning to not modify the file manually.
 
 2014-03-13  Joerg Wunsch <j.gnu@uriah.heep.sax.de>
 
diff --git a/avrdude.conf.in b/avrdude.conf.in
index ffe3d45b..ec9fc655 100644
--- a/avrdude.conf.in
+++ b/avrdude.conf.in
@@ -10,6 +10,10 @@
 # identifies which part AVRDUDE is going to be programming and must match
 # one of the parts' "id" parameter.
 #
+# DO NOT MODIFY THIS FILE.  Modifications will be overwritten the next
+# time a "make install" is run.  For user-specific additions, use the
+# "-C +filename" commandline option.
+#
 # Possible entry formats are:
 #
 #   programmer