The cov-emit command parses a source file and outputs it into a
directory (emit repository) that can later be analyzed with
cov-analyze. The cov-emit command is typically
called by cov-translate, which is in turn typically called by
cov-build (cov-emit is a low-level command and
is not normally called directly). The cov-emit command defines the
__COVERITY__ preprocessor symbol.