Hi, I found a bug in gdb-20011002/gdb/configure.in, line 748 . When you execute 'gcc -Wzzz' it will bark "gcc: No inout files specified", when you execute 'gcc -Wzzz dummy.c' it will bark "cc1: Invalid option `-Wzzz'" So, in order to verify whether a particular option is acceptable one has to (1) provide input file, (2) do grep on correct string. Thanks, Aleksey