I don't think it would warrant a backport since we adjusted our backport policy to be stricter. It doesn't seem like a major issue, and there is a noted workaround - removing the //line comments generated by Ragel.
Hey, I encounter a problem that could share the same cause, seems to me the coverprofile generation is broken with Go 1.11 when there are line directives. The column numbers are set to 0 in the output file, which can lead to issues when parsing this file. The workaround can't work for us since we do want to run tests against these instrumented files. Let me know if I should open another issue, I don't want to hijack this one.