On command line, a failed emerge will produce a log file with the naming convention:

/var/log/portage/CAT:PKG-PkgVer:ISODATE-ISOTIME.log

The presence of the colons in the file name prevent the simple operation of copy/pasting filepath into Jira bug reports to attach log file. Jira reports ":" character is unacceptable. User has to manually move/rename file in order to attach to bug reports.