unrecognizable insn building php4

[Chris Gorman <chris@cgnet.ca>]

Does anyone know how to go about debugging an unrecognisable insn error?  
The build output follows.

  2287  /bin/sh /usr/src/php4-4.0.4.5rc6/apache-build/libtool --silent
--mode=compile gcc  -I. -I/usr/src/php4-4.0.4.5rc6/ext/standard
-I/usr/src/php4-4.0.4.5rc6/apache-build/main -I/usr/src/php4-4.0.4.5rc6
-I/usr/include/apache-1.3 -I/usr/src/php4-4.0.4.5rc6/apache-build/Zend
-I/usr/include/freetype -I/usr/include/c-client -I/usr/include/mysql
-I/usr/include/ucd-snmp -I/usr/src/php4-4.0.4.5rc6/apache-build/TSRM
-I/usr/src/php4-4.0.4.5rc6/main
-I/usr/src/php4-4.0.4.5rc6/Zend -I/usr/src/php4-4.0.4.5rc6/TSRM
-DLINUX=22 -DEAPI -DTARGET="apache" -DUSE_HSREGEX -DUSE_EXPAT
-D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64 -O2 -Wall  -c
/usr/src/php4-4.0.4.5rc6/ext/standard/dns.c
  2288  /usr/src/php4-4.0.4.5rc6/ext/standard/dns.c: In function
`php_if_getmxrr':
  2289  /usr/src/php4-4.0.4.5rc6/ext/standard/dns.c:318: internal
error--unrecognizable insn:
  2290  (insn 825 824 314 (set (reg:SI 0 r0)
  2291          (umin:SI (reg/v:SI 0 r0)
  2292              (const_int 8192 [0x2000]))) -1 (nil)
  2293      (nil))
  2294  make[4]: *** [dns.lo] Error 1

I can hack around in dns.c, but IIRC the last time I got an insn error
(sendmail), it was a compiler problem.  If this one is too, I won't make
too much headway with dns.c.  Anyone have suggestions on how to debug
this?

Thanks
Chris