Re: Do we have free bits in the info pointer itself?

2016-09-16 Thread Florian Weimer
* Ryan Newton: > Our heap object header is one word -- an info table pointer > . > > Well, a 64 bit info table pointer leaves *at least* 16 high bits inside the > object header for other purposes, right? x86_64 has signed

Re: Is Safe Haskell intended to allow segfaults?

2016-09-16 Thread Florian Weimer
* Mikhail Glushenkov: > Hi, > > On 9 August 2016 at 01:32, David Terei wrote: >> I imagine in Java, that I can construct an invalid pointer in foreign >> code, and then cause segfaults without the Java code having any >> issues. Just guessing at this, so very interested to

Re: Add a signaling Nans rts option to ghc?

2016-09-16 Thread Carter Schonwald
IEEE standard specify infinities as distinguished from NAN. Not that the IEEE standard always makes the best choices (semantics of min and max being the naughtiest ). But to the extent that hardware supoorts toggling what values trigger failure it should be reasonably toggle -able For Intel

Re: -fno-warn lines in the lexer can be removed with Alex 3.1.5

2016-09-16 Thread Ben Gamari
Ömer Sinan Ağacan writes: > I was working on the lexer today and realized that we can now remove > -fno-warn lines in the lexer if we're OK with requiring Alex >=3.1.5. No objection from me; 3.1.5 was released nearly a year ago and it's easy enough to update. Cheers, -

Re: Add a signaling Nans rts option to ghc?

2016-09-16 Thread Niklas Hambüchen
Count me in as interested, I'd appreciate a feature to notice accidental NaNs in my code. ___ ghc-devs mailing list ghc-devs@haskell.org http://mail.haskell.org/cgi-bin/mailman/listinfo/ghc-devs

Re: Add a signaling Nans rts option to ghc?

2016-09-16 Thread Ben Gamari
Carter Schonwald writes: > Hello All! > I had some interesting conversations yesterday with a few folks and the > take away was that I might experiment with adding an off by default rts > flag that on applicable architectures that makes all floating point >

Add a signaling Nans rts option to ghc?

2016-09-16 Thread Carter Schonwald
Hello All! I had some interesting conversations yesterday with a few folks and the take away was that I might experiment with adding an off by default rts flag that on applicable architectures that makes all floating point computations that yield Nans signaling , plus mayve some HS side hooks to