On Mon, Aug 8, 2016 at 8:46 PM, Mikhail Glushenkov <mikhail. glushen...@gmail.com> wrote: > > Yes, this can be done with JNI, see e.g. [1]. Additionally, by using > sun.misc.Unsafe [2], one can cause segfaults even from pure Java. > [1] https://www.cs.princeton.edu/~appel/papers/safejni.pdf > [2] http://www.inf.usi.ch/faculty/lanza/Downloads/Mast2015a.pdf
Ah, I see. I thought that, ruling out FFI, that you couldn't segfault with pure Java code. Good to know about the unsafe interface. On Mon, Aug 8, 2016 at 7:32 PM, David Terei <davidte...@gmail.com> wrote: > > If you have the energy, it'd be great to put some of this thinking > into a wiki page (https://ghc.haskell.org/trac/ghc/wiki/SafeHaskell) > and flesh out a first approximation of what IO API's cause issues. Is > it just Ptr not carrying bounds around with it? Maybe, but then we > need to secure how Ptr's can be created, which excludes FFI returning > Ptr's. > Yes, we can add a Wiki page. Btw I was thinking more of kicking FFI/peek/poke outside of the Safe bubble, not changing their operational behavior. First of all, it's nigh impossible to lock down FFI calls. When someone, e.g. Bob Harper <https://existentialtype.wordpress.com/2012/08/14/haskell-is-exceptionally-unsafe/>, points out a problem in Haskell, we sometimes respond "hey, *Safe Haskell* is the real objet d'art! It's a safe language." Yet it isn't really a full *language* if people cannot write and run programs in it! (Because every program must be ultimately be `main::IO()`.) Kicking out segfaulty features would still leave a safe language that people can write complete programs in. Best, -Ryan
_______________________________________________ ghc-devs mailing list ghc-devs@haskell.org http://mail.haskell.org/cgi-bin/mailman/listinfo/ghc-devs
