As part of the Build program's configuration efforts, it executes the devtools/bin/configure.sh script. That script attempts to help you automatically configure db(3) and a resolver library for your system. First, the standard include and library directories are searched for db(3) support, and, if found, NEWDB is defined for confMAPDEF.

Second, configure.sh searches for an appropriate resolver library and modifies confLIBS appropriately:

-lresolv               for BIND before V4.9
-lresolv -l44bsd       for BIND V4.9.x
-lbind                 for BIND V8.x

This -S Build switch prevents these two automatic configuration strategies.