Recently introduced incompatibility?

Hi,

I just installed glibc from cvs and noticed an error during make 
install. Right after make installed libpthread.so all files linked to 
that library started segfaulting (including make itself). Gdb suggested 
problems in __pthread_initialize_minimal_internal. I used 
LD_LIBRARY_PATH to point to another nptl library and this workaround 
helped me complete the install. Now all programs linked to libpthread 
work normally again, but segfault when LD_LIBRARY_PATH points to an 
older version.
I guess the nptl library required another part of glibc (libc.so maybe?) 
to be installed before it could initialize. Is this incompatibility 
supposed to exist? (If so, shouldn't the make install order be changed?)
My previous glibc install was from 10-10.