I recently tried libmapping libc_r to libthr on my -current system from Sep 10, and ran into a lot of problems with signal delivery. Specifically, mozilla hung in the sigwait state when I opened a bunch of tabs in quick succession, and other processes did not respond to signals using ^C/^Z/^\, or even kill -HUP. The problems went away when I reverted to libc_r.
Kris
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