libpthread breaking various pkg builds

[Mark Davies <mark%ecs.vuw.ac.nz@localhost>]

Various pkgsrc builds are failing on current/i386 with errors like 
this:

multimedia/xine-lib:
  sed -e /CODEC_ID_PCM_S16LE/,/CODEC_ID_DVD_SUBTITLE/'! d; s/^[ 
\t]*//; s/[=,].*//; /^$/ d'
 >avcodec_audio.list
/usr/pkg/bin/perl mkcodeclist.pl avcodec_video.list xine_video.list 
ff_video_list.h
perl: mprotect stack: gmake[3]: *** [ff_video_list.h] Segmentation 
fault


devel/pango:
gmake[3]: Leaving directory 
`/local/src/work/pkgsrc/devel/pango/work.i386/pango-1.28.3'
  GEN    s-enum-types-h
perl: mprotect stack: [1]   Segmentation fault      (cd . && glib-
mk...
gmake[2]: *** [s-enum-types-h] Error 139


databases/mysql51-server:
gmake[2]: Leaving directory 
`/local/src/work/pkgsrc/databases/mysql51-server/work.i386/mysq
l-5.1.54/sql'
./gen_lex_hash > lex_hash.h-t
gen_lex_hash: mprotect stack: /usr/pkg/bin/bash: line 1: 14462 
Segmentation fault      ./gen_lex_hash > lex_hash.h-t
gmake[1]: *** [lex_hash.h] Error 139



reverting libpthread from one built on Dec20 to one from Dec3 fixes 
the builds.

presumably this is the relevant change:
http://mail-index.netbsd.org/source-
changes/2010/12/18/msg016072.html

cheers
mark