The package 'devel/glib2' (version 2.12.3) doesn't build on my Linux
system - CentOS 4.1 (RHEL clone) i386.  The problem seems to be
'patch-aa', which introduces a CFLAGS, '-pthreads', which the system
doesn't recognize, and an LDFLAGS, '-lpthreads', for a library not
present.  For my Linux system, those values should be '-pthread' and
'-lpthread', respectively.  Removing 'patch-aa' fixes the 
"pthreads/pthread" problem, but introduces another.  I can provide
more details for anyone interested.

DGS