When building with --nonshared-binary=smbd/smbd:

...
[3139/3620] Linking default/source3/smbd/smbd
...
default/source4/heimdal/lib/hx509/sel-lex_116.o: In function `yy_get_previous_state':
/usr/build/packages/samba-4.5/bin/../source4/heimdal/lib/hx509/sel-lex.c:1122:multiple definition of `yyin'
default/source3/rpc_server/mdssvc/sparql_lexer_28.o:/usr/build/packages/samba-4.5/bin/sparql_lexer.c:1149:first defined here
...

The fix is to use namespace prefixes in the parser and the lexer as described here:
<https://www.gnu.org/software/bison/manual/html_node/Multiple-Parsers.html>

Patch to follow...