Build of tests fails on FreeBSD 12.0 #18869

Building on FreeBSD gives a huge number of linker errors while building test_bitcoin:

user@medea:~/src/bitcoin % gmake                                                                          
Making all in src                                                                                         
gmake[1]: Entering directory '/usr/home/user/src/bitcoin/src'                                             
gmake[2]: Entering directory '/usr/home/user/src/bitcoin/src'                                             
  CXXLD    test/test_bitcoin                                                                              
/usr/bin/ld: error: undefined symbol: BasicTestingSetup::BasicTestingSetup(std::__1::basic_string<char, st
d::__1::char_traits<char>, std::__1::allocator<char> > const&)                                            
>>> referenced by amount_tests.cpp:13 (test/amount_tests.cpp:13)                                          
>>>               test/test_bitcoin-amount_tests.o:(amount_tests::MoneyRangeTest_invoker())               
                                                                                                          
/usr/bin/ld: error: undefined symbol: BasicTestingSetup::BasicTestingSetup(std::__1::basic_string<char, st
d::__1::char_traits<char>, std::__1::allocator<char> > const&)                                            
>>> referenced by amount_tests.cpp:22 (test/amount_tests.cpp:22)                                       
>>>               test/test_bitcoin-amount_tests.o:(amount_tests::GetFeeTest_invoker())                   
                                                                                                          
/usr/bin/ld: error: undefined symbol: BasicTestingSetup::BasicTestingSetup(std::__1::basic_string<char, st
d::__1::char_traits<char>, std::__1::allocator<char> > const&)                                            
>>> referenced by amount_tests.cpp:89 (test/amount_tests.cpp:89)                                          
>>>               test/test_bitcoin-amount_tests.o:(amount_tests::BinaryOperatorTest_invoker())           
                                                                                                          
/usr/bin/ld: error: undefined symbol: BasicTestingSetup::BasicTestingSetup(std::__1::basic_string<char, st
d::__1::char_traits<char>, std::__1::allocator<char> > const&)                                            
>>> referenced by flatfile_tests.cpp:15 (test/flatfile_tests.cpp:15)                                      
>>>               test/test_bitcoin-flatfile_tests.o:(flatfile_tests::flatfile_filename_invoker())        
                                                                                                          
/usr/bin/ld: error: too many errors emitted, stopping now (use -error-limit=0 to see all errors)          
c++: error: linker command failed with exit code 1 (use -v to see invocation)                             
gmake[2]: *** [Makefile:8553: test/test_bitcoin] Error 1                                               
gmake[2]: Leaving directory '/usr/home/user/src/bitcoin/src'                                              
gmake[1]: *** [Makefile:17674: all-recursive] Error 1                                                     
gmake[1]: Leaving directory '/usr/home/user/src/bitcoin/src'                                              
gmake: *** [Makefile:781: all-recursive] Error 1   

bitcoind itself, as well as the other cli tools, is built succesfully.

Which version of freebsd? On a fresh 12.1 I get no linker errors (only boost compile warnings)

https://cirrus-ci.com/task/5728076485099520?command=make#L1335

12.0-RELEASE-p10 according to freebsd-version

If you say it works fine with 12.1, ok good, I won't spend anymore time on this. I can build bitcoind for now and will see about the tests again when I've upgraded the distribution.

Which commit is this? The BasicTestingSetup(const std::string&) constructor no longer exists in current master. Does make clean, or similar way to clean old object files help?

Yes, I did a make clean.

Edit: deleted everything and started from a clean git tree, as we do.

Ok, building from an entirely new git tree seems to work. No idea what the problem was.