diff --git a/winsup/cygwin/ChangeLog b/winsup/cygwin/ChangeLog
index 5bf6c4e6b..911263126 100644
--- a/winsup/cygwin/ChangeLog
+++ b/winsup/cygwin/ChangeLog
@@ -1,3 +1,10 @@
+2006-02-05  Corinna Vinschen  <corinna@vinschen.de>
+
+	* include/features.h: Add comment to explain what's going to happen
+	here at one point.
+	* include/sys/stdio.h: Guard getline and getdelim prototypes with
+	_GNU_SOURCE to avoid collision with old-style declarations.
+
 2006-02-05  Corinna Vinschen  <corinna@vinschen.de>
 
 	* environ.cc (struct parse_thing): Add transparent_exe option.
diff --git a/winsup/cygwin/include/features.h b/winsup/cygwin/include/features.h
index 0fcc90bfd..69c12d22c 100644
--- a/winsup/cygwin/include/features.h
+++ b/winsup/cygwin/include/features.h
@@ -14,4 +14,22 @@ details. */
 #include <sys/cdefs.h>
 #include <sys/features.h>
 
+/* Various options should be defined here, but the framework to do this
+   is not laid down so far.  Especially notable are the following defines,
+   which can be used by the application to switch on or off various 
+   datatypes and function prototypes:
+   
+     _BSD_SOURCE   to include pure BSD functions which are not defined
+                   under POSIX.
+
+     _POSIX_SOURCE if the application requests a POSIX compatible system.
+
+     _XOPEN_SOURCE if X/Open functions and datatypes are requested.  This
+                   option includes _POSIX_SOURCE.
+
+     _GNU_SOURCE   to turn on GNU extensions which might collide with defines
+                   used in application or library headers.  This option
+		   includes _BSD_SOURCE, _XOPEN_SOURCE and _POSIX_SOURCE.
+*/
+
 #endif /* _FEATURES_H */
diff --git a/winsup/cygwin/include/sys/stdio.h b/winsup/cygwin/include/sys/stdio.h
index 8d002ddba..7cc6f09f1 100644
--- a/winsup/cygwin/include/sys/stdio.h
+++ b/winsup/cygwin/include/sys/stdio.h
@@ -28,8 +28,10 @@ details. */
 
 __BEGIN_DECLS
 
+#ifdef _GNU_SOURCE
 ssize_t	_EXFUN(getline, (char **, size_t *, FILE *));
 ssize_t	_EXFUN(getdelim, (char **, size_t *, int, FILE *));
+#endif /* _GNU_SOURCE */
 
 __END_DECLS