The expat update introduces unsightly build warnings:

gcc -Wno-unused-result -Wsign-compare -Wunreachable-code -DNDEBUG -g -fwrapv -O3 -Wall -std=c99 -Wextra -Wno-unused-result -Wno-unused-parameter -Wno-missing-field-initializers -Wstrict-prototypes -Werror=implicit-function-declaration -I./Include/internal -DHAVE_EXPAT_CONFIG_H=1 -DXML_POOR_ENTROPY=1 -DUSE_PYEXPAT_CAPI -I/Users/nad/Projects/PyDev/active/dev/3x/source/Modules/expat -I./Include -I. -I/Users/nad/Projects/PyDev/active/dev/3x/source/Include -I/Users/nad/Projects/PyDev/active/dev/3x/source -c /Users/nad/Projects/PyDev/active/dev/3x/source/Modules/expat/xmlparse.c -o build/temp.macosx-10.14-x86_64-3.9/Users/nad/Projects/PyDev/active/dev/3x/source/Modules/expat/xmlparse.o -Wno-implicit-fallthrough
/Users/nad/Projects/PyDev/active/dev/3x/source/Modules/expat/xmlparse.c:3027:11: warning: code will never be executed
      [-Wunreachable-code]
          parser->m_characterDataHandler(parser->m_handlerArg, parser->m_dataBuf, 0);
          ^~~~~~
/Users/nad/Projects/PyDev/active/dev/3x/source/Modules/expat/xmlparse.c:3026:18: note: silence by adding parentheses to
      mark code as explicitly dead
        else if (0 && parser->m_characterDataHandler)
                 ^
                 /* DISABLES CODE */ ( )
/Users/nad/Projects/PyDev/active/dev/3x/source/Modules/expat/xmlparse.c:3728:9: warning: code will never be executed
      [-Wunreachable-code]
        parser->m_characterDataHandler(parser->m_handlerArg, parser->m_dataBuf, 0);
        ^~~~~~
/Users/nad/Projects/PyDev/active/dev/3x/source/Modules/expat/xmlparse.c:3727:16: note: silence by adding parentheses to
      mark code as explicitly dead
      else if (0 && parser->m_characterDataHandler)
               ^
               /* DISABLES CODE */ ( )
2 warnings generated.