[marek@nos proc]$ fpc proc05
Free Pascal Compiler version 1.9.4 [2004/05/30] for i386
Copyright (c) 1993-2004 by Florian Klaempfl
Target OS: Linux for i386
Compiling proc05.pas
proc05.pas(12,8) Error: Duplicate identifier "x"
proc05.pas(25,4) Fatal: There were 1 errors compiling module, stopping