FreeBSD: Examples/buildsystem-capi.llbuild: ld: error: undefined symbol: backtrace

[etcwilde]

FAIL: llbuild :: Examples/buildsystem-capi.llbuild (64 of 214)
******************** TEST 'llbuild :: Examples/buildsystem-capi.llbuild' FAILED ********************
Exit Code: 1

Command Output (stdout):
--
# RUN: at line 3
/home/ewilde/Work/SwiftBootstrap-Stages/stage2/usr/bin/clang++ -o /home/ewilde/Work/Swift-Project/build/buildbot_freebsd/llbuild-freebsd-x86_64/tests/Examples/Output/buildsystem-capi.llbuild.tmp.exe -x c++ /home/ewilde/Work/Swift-Project/llbuild/examples/c-api/buildsystem/main.c -I /home/ewilde/Work/Swift-Project/llbuild/products/libllbuild/include -lllbuild -lllbuildBuildSystem -lllbuildCore -lllbuildBasic -lllvmSupport -lllvmDemangle -L /home/ewilde/Work/Swift-Project/build/buildbot_freebsd/llbuild-freebsd-x86_64/lib -Werror -Xlinker /usr/local/lib/libsqlite3.so -lcurses -lpthread
# executed command: /home/ewilde/Work/SwiftBootstrap-Stages/stage2/usr/bin/clang++ -o /home/ewilde/Work/Swift-Project/build/buildbot_freebsd/llbuild-freebsd-x86_64/tests/Examples/Output/buildsystem-capi.llbuild.tmp.exe -x c++ /home/ewilde/Work/Swift-Project/llbuild/examples/c-api/buildsystem/main.c -I /home/ewilde/Work/Swift-Project/llbuild/products/libllbuild/include -lllbuild -lllbuildBuildSystem -lllbuildCore -lllbuildBasic -lllvmSupport -lllvmDemangle -L /home/ewilde/Work/Swift-Project/build/buildbot_freebsd/llbuild-freebsd-x86_64/lib -Werror -Xlinker /usr/local/lib/libsqlite3.so -lcurses -lpthread
# .---command stderr------------
# | ld: error: undefined symbol: backtrace
# | >>> referenced by Signals.cpp
# | >>>               Signals.cpp.o:(llvm::sys::PrintStackTrace(llvm::raw_ostream&)) in archive /home/ewilde/Work/Swift-Project/build/buildbot_freebsd/llbuild-freebsd-x86_64/lib/libllvmSupport.a
# | clang++: error: linker command failed with exit code 1 (use -v to see invocation)
# `-----------------------------
# error: command failed with exit status: 1

--

********************

[etcwilde]

This may just be a matter of adding -lbacktrace to the test.