broken xterm and portupgrade stuck in a loop

[h]

on a 4.10-STABLE system on an old celeron 400 laptop, i have XFree 4.4:

~ > ls /var/db/pkg/X
XFree86-4.4.0_1,1                       XFree86-font75dpi-4.3.0
XFree86-FontServer-4.3.0_2              XFree86-fontCyrillic-4.3.0
XFree86-NestServer-4.4.0                XFree86-fontDefaultBitmaps-4.3.0
XFree86-PrintServer-4.4.0               XFree86-fontEncodings-4.3.0
XFree86-Server-4.3.0_10                 XFree86-fontScalable-4.3.0
XFree86-VirtualFramebufferServer-4.4.0  XFree86-libraries-4.4.0_1
XFree86-clients-4.3.0_3                 XFree86-manuals-4.4.0
XFree86-documents-4.4.0                 Xaw3d-1.5
XFree86-font100dpi-4.3.0                Xft-2.1.2

but when i try to start a xterm in X, i get:

/usr/libexec/ld-elf.so.1: Shared object "libexpat.so.4" not found, required by 
"xterm"

but libexpat is actually installed: /var/db/pkg/expat-1.95.8

when i build any port, i get:

===>  Vulnerability check disabled, database not found

at the beginning of make. i don't know if that's related.

so i want to try portupgrade -a after pkgdb -F returns no error and my ports 
tree updated.

portupgrade produces no output and seems to be stuck in a loop. so i 
repeatedly hit ps ax | grep ports to see what it's doing and here is what i 
get:

sidewinder# ps ax | grep ports
93129  v1  S+     0:00.01 sh -c cd /usr/ports/audio/cdparanoia && make -V 
PKGNA
sidewinder# ps ax | grep ports
93158  v1  S+     0:00.01 sh -c cd /usr/ports/audio/esound && make -V PKGNAME 
2
sidewinder# ps ax | grep ports
93187  v1  S+     0:00.00 sh -c cd /usr/ports/audio/libaudiofile && make -V 
PKG
sidewinder# ps ax | grep ports
93216  v1  S+     0:00.00 sh -c cd /usr/ports/converters/libiconv && make -V 
PK
sidewinder# ps ax | grep ports
93245  v1  S+     0:00.01 sh -c cd /usr/ports/devel/ORBit2 && make -V PKGNAME 
2
sidewinder# ps ax | grep ports
93274  v1  S+     0:00.01 sh -c cd /usr/ports/devel/autoconf253 && make -V 
PKGN
sidewinder# ps ax | grep ports
93297  v1  S+     0:00.01 sh -c cd /usr/ports/devel/automake15 && make -V 
PKGNA
sidewinder# ps ax | grep ports
93341  v1  S+     0:00.01 sh -c cd /usr/ports/devel/fam && make -V PKGNAME 
2>/d
sidewinder# ps ax | grep ports
93370  v1  S+     0:00.01 sh -c cd /usr/ports/devel/gconf2 && make -V PKGNAME 
2
sidewinder# ps ax | grep
  330  v1  S+     0:00.01 sh -c cd /usr/ports/multimedia/gstreamer-plugins &&
  508  v1  S+     0:00.33 make 
PARENT_CHECKED=/usr/ports/devel/gmake /usr/ports
  517  v1  S+     0:00.00 /bin/sh -ec 
checked="/usr/ports/devel/gmake /usr/port
  518  v1  S+     0:00.01 /bin/sh -ec 
checked="/usr/ports/devel/gmake /usr/port
  563  v1  R+     0:00.09 make 
PARENT_CHECKED=/usr/ports/devel/pkgconfig  /usr/
sidewinder# ps ax | grep ports
  330  v1  S+     0:00.01 sh -c cd /usr/ports/multimedia/gstreamer-plugins &&
  508  v1  S+     0:00.33 make 
PARENT_CHECKED=/usr/ports/devel/gmake /usr/ports
  517  v1  S+     0:00.00 /bin/sh -ec 
checked="/usr/ports/devel/gmake /usr/port
  518  v1  S+     0:00.01 /bin/sh -ec 
checked="/usr/ports/devel/gmake /usr/port
sidewinder# ps ax | grep ports
  330  v1  S+     0:00.01 sh -c cd /usr/ports/multimedia/gstreamer-plugins &&
sidewinder# ps ax | grep ports
  330  v1  S+     0:00.01 sh -c cd /usr/ports/multimedia/gstreamer-plugins &&
  776  v1  R+     0:00.00 /usr/bin/grep -qwv /usr/ports/dev

as i'm writing this it's been running 45 minutes. ports names seem to come 
back. is that normal ? how long should i leave portupgrader speechless before 
i consider it crashed ? how do i fix my ports tree ?