Soft assertions. LLDB provides lldb_assert() as a soft alternative to cover the middle ground of situations that indicate a recoverable bug in LLDB. In a Debug configuration lldb_assert() behaves like assert(). In a Release configuration it will print a warning and encourage the user to file a bug report, similar to LLVM’s crash handler, and then return execution.
However, currently lldb_assert doesn't behave they way it's being described there: it doesn't abort in a debug/assert build.