I'm pretty sure that code compiled against glib can trigger this.

since deleting pth and trying to make a clean environment,
pkgsrc/x11/gtk now won't re-compile for me. It dies in a conftest on glib,
which fails with the pthread next != null assertion.

	# ./conftest
	assertion "next != 0" failed: 
		file "/usr/src/lib/libpthread/pthread_run.c", line 115, 
		function "pthread__next"
	Abort trap (core dumped)


ldd shows /usr/pkg/lib/libgthread.so (from glib) depends on libpthread.so  

so if somebody can help make the pkgsrc/devel/glib/ re-build link static to
pthread, I'd hope a lot of userland apps will suddenly stop having this
assertion failure.

cheers

	-George