Build completes, but with errors

I worked from the Building LibreOffice on OS X web page & chose the “minimal setup” build. Make ran 
for ~4 hr. The last few lines of build.log are:


testTdf99074::Import finished in: 147ms
File tested,Execution Time (ms)
tdf99140.docx:
107
testTdf99140::Import finished in: 117ms
/Users/ml/lo/core/sw/qa/extras/ooxmlimport/ooxmlimport.cxx:1884: Assertion
Test name: textboxWpsOnly::Import
equality assertion failed
- Expected: 2
- Actual  : 0

Failures !!!
Run: 220   Failure total: 1   Failures: 1   Errors: 0
2016-09-15 20:16:45.309 cppunittester[84771:1171679] *** -[NSAutoreleasePool release]: This pool 
has already been released, do not drain it (double release).

Error: a unit test failed, please do one of:
make CppunitTest_sw_ooxmlimport CPPUNITTRACE="lldb --"       # for interactive debugging on OS X
make CppunitTest_sw_ooxmlimport VALGRIND=memcheck            # for memory checking

make[1]: *** [/Users/ml/lo/core/workdir/CppunitTest/sw_ooxmlimport.test] Error 1
make: *** [build] Error 2


This is my first build of LO. I’m not sure how to proceed from here. Should I try one of the make 
CppunitTest options? Which one? Do I have a viable build?

Any assistance appreciated, thanks

ML