LLVM breaks buildworld

cd /usr/obj
rm -f usr
cd /usr/src
svn update
make buildworld
(wait a long time)

===> lib/clang/libllvm (all)
llvm-tblgen -gen-asm-matcher  -I /usr/src/contrib/llvm/include -I /usr/src/contrib/llvm/lib/Target/Mips  -d MipsGenAsmMatcher.inc.d -o MipsGenAsmMatcher.inc  /usr/src/contrib/llvm/lib/Target/Mips/Mips.td
Included from /usr/src/contrib/llvm/lib/Target/Mips/Mips.td:57:
Included from /usr/src/contrib/llvm/lib/Target/Mips/MipsInstrInfo.td:3010:
/usr/src/contrib/llvm/lib/Target/Mips/MipsDSPInstrInfo.td:1142:25: error: Couldn't find class 'SHRD_QB_ENC'
def SHRL_QB : DspMMRel, SHRD_QB_ENC, SHRL_QB_DESC;
                        ^
*** Error code 1

Stop.
make[6]: stopped in /usr/src/lib/clang/libllvm
*** Error code 1

Stop.
make[5]: stopped in /usr/src/lib/clang
*** Error code 1

Stop.
make[4]: stopped in /usr/src/lib
*** Error code 1

Stop.
make[3]: stopped in /usr/src
*** Error code 1

Stop.
make[2]: stopped in /usr/src
*** Error code 1

Stop.
make[1]: stopped in /usr/src
*** Error code 1

Stop.
make: stopped in /usr/src

-- 
Steve
20170425 https://www.youtube.com/watch?v=VWUpyCsUKR4
20161221 https://www.youtube.com/watch?v=IbCHE-hONow