Draft: Backport !6238 to ghc-9.0 (Doc: warnings: add `:since:` fields for warnings of GHC 6/7/8)
Backport !6238 (closed) (Doc: warnings: add :since:
fields for warnings of GHC 6/7/8)
Cherry-picked the commits of !6238 (closed) and resolved conflicts in favor of adding docs that were missing in the 9.0 docs:
- -Wdefault
- -Wauto-orphans
- -Wmissing-space-after-bang