cc1: warning: changing search order for system directory "/usr/local/i
+nclude" 
cc1: warning: as it has already been specified as a non-system directo
+ry 
perlio.c: In function `PerlIO_ungetc': 
perlio.c:4441: warning: unused variable `Perl___notused' 
...
[download]

These are actual warnings, not errors. They shouldn't prevent perl from being compiled.

If i try and use the command cpan

What are you trying to do with the cpan command?

Abigail