-s Do not echo any commands as they are executed
"debug info" means the extra symbols containing things like mapping addresses to function names, positions in source code, etc, all the stuff necessary for a debugger like e.g. lldb(1) to show you useful and readable info analyzing a compiled binary program at runtime or "post mortem" from aI understood that you want to hide information during build on screen.
.core
file. FreeBSD by default creates this info, but puts it in separate files. There are knobs to completely disable it, so the first answer in this thread is the correct one.