>No, it's not. It's a set of fullpath_length. Sorry something is not clear for me. what does this mean int i; i = 0; I defined a variable and used it. If fullpath_length is not really used, I should not receive any error by commenting that. Like this: int length/*, fullpath_length*/; But I get this error syscall.c:1023:3: error: ‘fullpath_length’ undeclared (first use in this function) the line it points is fullpath_length = strlen(fullpath); // Naderan *Mahmood; ----- Original Message ----- From: Andrew Haley <aph@xxxxxxxxxx> To: Mahmood Naderan <nt_mahmood@xxxxxxxxx> Cc: gcc <gcc-help@xxxxxxxxxxx> Sent: Tuesday, July 12, 2011 10:43 PM Subject: Re: variable ‘something’ set but not used [-Wunused-but-set-variable] On 07/12/2011 07:12 PM, Mahmood Naderan wrote: >> The message is correct. fullpath_length is set, but not used. > > Hi > What is this then > > fullpath_length = strlen(fullpath); // variable is used here > > isn't a usage of fullpath_length? No, it's not. It's a set of fullpath_length. Andrew.