Warn about usage of `OPTIONS_GHC -XLanguageExtension`
We should warn if suspicious flags are given in OPTIONS_GHC pragmas; in particular, if any -XLanguage flag is used.
Trac metadata
| Trac field | Value |
|---|---|
| Version | 6.8.2 |
| Type | FeatureRequest |
| TypeOfFailure | OtherFailure |
| Priority | normal |
| Resolution | Unresolved |
| Component | Compiler |
| Test case | |
| Differential revisions | |
| BlockedBy | |
| Related | |
| Blocking | |
| CC | |
| Operating system | Unknown |
| Architecture | Unknown |