* Omari Norman
Is there a way to determine whether a module has been marked safe by GHC for purposes of Safe Haskell?
The GHC 7.4 docs say that if I compile a module and I don't use the -XSafe or -XTrustworthy flag, GHC will automatically figure out whether the module would have compiled with -XSafe and, if so, marks the module as safe. Where does GHC record this determination? It doesn't seem to show up in ghc-pkg dump (there you can see trusted packages, but I am looking for safe-inferred status for modules.) ghc --show-iface seems to come up dry too.
% ghc --show-iface /opt/ghc761/lib/ghc-7.6.1/filepath-1.3.0.1/System/FilePath.hi | grep trusted: trusted: safe
I know Haddock shows this information but sometimes it says "Safe Haskell: None". I have no idea what this means so I was wondering what GHC itself says.
It's what GHC says — see the SafeHaskellMode type in https://github.com/ghc/ghc/blob/master/compiler/main/DynFlags.hs It seems that None means that the module was compile with Safe Haskell disabled (-fno-safe-infer), but I'm not sure what the semantics of this is. Perhaps it's equivalent to Unsafe? Roman