[Haskell-cafe] [ANNOUNCE] GHC 8.4.3 released

[Viktor Dukhovni]

On Tue, May 29, 2018 at 04:07:23PM -0400, Ben Gamari wrote:

> The GHC team is pleased to announce the availability of GHC 8.4.3. The
> source distribution, binary distributions, and documentation for this
> release are available at
> 
>     https://downloads.haskell.org/~ghc/8.4.3

While there's no binary distribution for FreeBSD at haskell.org,
as of June 30 there's a FreeBSD ghc-8.4.3 port.  

    https://svnweb.freebsd.org/ports/head/lang/ghc/Makefile?view=log

FWIW, while building it I saw a compiler warning:

    libraries/Cabal/Cabal/Distribution/Simple/Program/Builtin.hs:62:1: warning: [-Wunused-imports]
	The import of ‘System.FilePath’ is redundant
	  except perhaps to import instances from ‘System.FilePath’
	To import instances alone, use: import System.FilePath()
       |
    62 | import System.FilePath (takeDirectory)
       | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

one thing that puzzles me is that on MacOS/X and Linux running
Haskell code has a fixed virtual size of 1TB, while on FreeBSD the
"vsz" reported by "ps", "top", ... is rought what you'd expect given
the actual memory usage of the program plus overhead from generational
GC.

I am curious as to why the process memory model is platform-dependent
in this manner.  It seems as though on many platforms the RTS gives
the process a large virtul address space, and then allocates memory
by fauliting-in previously unused pages, whereas on FreeBSD brk(2)
(via sbrk() or malloc(), ...) is used to extend the process virtual
size on demand.

--
	Viktor.