Kotlin compiler prints warnings but, it would be wonderful if we could have them on a XML report

I'm curious what you'd use the report for?

we have our internal tools, like a Sonarqube

Do you use detekt or ktlint or new kotlin support in Sonarqube? I'd expect one of those to catch the issue too and you'd be able to view it that way instead.

sure we use detekt and we should use ktlint too

I suspect there's overlap between the two. So you're seeing warnings from compiler that detekt doesn't show? Hmm. Wonder if that's intentional. Warnings I've seen this far from compiler are easy to fix. Any reason you don't just mandate they be fixed now?