4.9-STABLE -> 5.x

Hi,


I'm trying to upgrade from 4.9-STABLE to -CURRENT and I thought it would
be best to go from 4.9 to 5.1-RELEASE and then 5.1-R to -CURRENT. I'm
getting the following errors during make buildworld:

cc -fpic -DPIC -O -pipe -mcpu=pentiumpro -DPTHREAD_KERNEL
-I/usr/src/lib/libpthread/../libc/include
-I/usr/src/lib/libpthread/thread
-I/usr/src/lib/libpthread/../../include
-I/usr/src/lib/libpthread/arch/i386/include
-I/usr/src/lib/libpthread/sys
-I/usr/src/lib/libpthread/../../libexec/rtld-elf -fno-builtin
-D_LOCK_DEBUG -D_PTHREADS_INVARIANTS -Wall
-I/usr/src/lib/libpthread/../libc/i386 -I/usr/src/lib/libpthread/thread
-c /usr/src/lib/libpthread/arch/i386/i386/thr_switch.S  -o thr_switch.So
cc -fpic -DPIC -O -pipe -mcpu=pentiumpro -DPTHREAD_KERNEL
-I/usr/src/lib/libpthread/../libc/include
-I/usr/src/lib/libpthread/thread
-I/usr/src/lib/libpthread/../../include
-I/usr/src/lib/libpthread/arch/i386/include
-I/usr/src/lib/libpthread/sys
-I/usr/src/lib/libpthread/../../libexec/rtld-elf -fno-builtin
-D_LOCK_DEBUG -D_PTHREADS_INVARIANTS -Wall  -c
/usr/src/lib/libpthread/sys/lock.c -o lock.So
building shared library libkse.so.1
thr_libc.So: In function `sigaction':
thr_libc.So(.text+0x54): multiple definition of `_sigaction'
thr_sigaction.So(.text+0x0): first defined here
thr_libc.So: In function `sigprocmask':
thr_libc.So(.text+0x34): multiple definition of `_sigprocmask'
thr_sigprocmask.So(.text+0x0): first defined here
*** Error code 1

Stop in /usr/src/lib/libpthread.
*** Error code 1

Stop in /usr/src/lib.
*** Error code 1

Stop in /usr/src.
*** Error code 1


Thanks,
Brad