merge from gcc

include/libiberty.h

@@ -86,6 +86,10 @@ extern char **dupargv (char **) ATTRIBUTE_MALLOC;
 
 extern void expandargv PARAMS ((int *, char ***));
 
+/* Write argv to an @-file, inserting necessary quoting.  */
+
+extern int writeargv PARAMS ((char **, FILE *));
+
 /* Return the last component of a path name.  Note that we can't use a
    prototype here because the parameter is declared inconsistently
    across different systems, sometimes as "char *" and sometimes as