Checking if your kit is complete...
Looks good
Writing Makefile for Sys::PortIO
cp PortIO.pm blib/lib/Sys/PortIO.pm
AutoSplitting blib/lib/Sys/PortIO.pm (blib/lib/auto/Sys/PortIO)
/home/cpanrun/build/5.6.1/bin/perl -I/home/cpanrun/build/5.6.1/lib/5.6.1/i686-linux-thread-multi -I/home/cpanrun/build/5.6.1/lib/5.6.1 /home/cpanrun/build/5.6.1/lib/5.6.1/ExtUtils/xsubpp  -typemap /home/cpanrun/build/5.6.1/lib/5.6.1/ExtUtils/typemap PortIO.xs > PortIO.xsc && mv PortIO.xsc PortIO.c
Please specify prototyping behavior for PortIO.xs (see perlxs manual)
gcc -c  -DUSE_REENTRANT_API -D_GNU_SOURCE -D_REENTRANT -fno-strict-aliasing -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64 -O2   -DVERSION=\"0.1\" -DXS_VERSION=\"0.1\" -fpic -I/home/cpanrun/build/5.6.1/lib/5.6.1/i686-linux-thread-multi/CORE  PortIO.c
Running Mkbootstrap for Sys::PortIO ()
chmod 644 PortIO.bs
rm -f blib/arch/auto/Sys/PortIO/PortIO.so
LD_RUN_PATH="" gcc  -shared PortIO.o  -o blib/arch/auto/Sys/PortIO/PortIO.so     
chmod 755 blib/arch/auto/Sys/PortIO/PortIO.so
cp PortIO.bs blib/arch/auto/Sys/PortIO/PortIO.bs
chmod 644 blib/arch/auto/Sys/PortIO/PortIO.bs
Manifying blib/man3/Sys::PortIO.3
PERL_DL_NONLAZY=1 /home/cpanrun/build/5.6.1/bin/perl -Iblib/arch -Iblib/lib -I/home/cpanrun/build/5.6.1/lib/5.6.1/i686-linux-thread-multi -I/home/cpanrun/build/5.6.1/lib/5.6.1 test.pl
test.p..............ok
All tests successful.
Files=1, Tests=1,  0 wallclock secs ( 0.32 cusr +  0.02 csys =  0.34 CPU)
Installing /home/cpanrun/build/5.6.1/lib/site_perl/5.6.1/i686-linux-thread-multi/auto/Sys/PortIO/PortIO.so
Installing /home/cpanrun/build/5.6.1/lib/site_perl/5.6.1/i686-linux-thread-multi/auto/Sys/PortIO/PortIO.bs
Installing /home/cpanrun/build/5.6.1/lib/site_perl/5.6.1/i686-linux-thread-multi/auto/Sys/PortIO/autosplit.ix
Installing /home/cpanrun/build/5.6.1/lib/site_perl/5.6.1/i686-linux-thread-multi/Sys/PortIO.pm
Installing /home/cpanrun/build/5.6.1/man/man3/Sys::PortIO.3
Appending installation info to /home/cpanrun/build/5.6.1/lib/5.6.1/i686-linux-thread-multi/perllocal.pod