Index: bison-2.5/lib/stdio.in.h
===================================================================
--- bison-2.5.orig/lib/stdio.in.h
+++ bison-2.5/lib/stdio.in.h
@@ -181,7 +181,9 @@ _GL_WARN_ON_USE (fflush, "fflush is not
    so any use of gets warrants an unconditional warning.  Assume it is
    always declared, since it is required by C89.  */
 #undef gets
+#if HAVE_RAW_DECL_GETS
 _GL_WARN_ON_USE (gets, "gets is a security hole - use fgets instead");
+#endif
 
 #if @GNULIB_FOPEN@
 # if @REPLACE_FOPEN@