[commit: packages/unix] master: Add comment regarding genericRaise use (ff1c16d)

[git at git.haskell.org]

Repository : ssh://git@git.haskell.org/unix

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/ff1c16d4ee0c4ca043bd99a5d6741ea2d53e7000/unix

>---------------------------------------------------------------

commit ff1c16d4ee0c4ca043bd99a5d6741ea2d53e7000
Author: Herbert Valerio Riedel <hvr at gnu.org>
Date:   Sun Jan 31 17:04:25 2016 +0100

    Add comment regarding genericRaise use


>---------------------------------------------------------------

ff1c16d4ee0c4ca043bd99a5d6741ea2d53e7000
 System/Posix/Signals.hsc | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/System/Posix/Signals.hsc b/System/Posix/Signals.hsc
index 222911a..971973e 100644
--- a/System/Posix/Signals.hsc
+++ b/System/Posix/Signals.hsc
@@ -290,6 +290,9 @@ foreign import ccall unsafe "killpg"
 raiseSignal :: Signal -> IO ()
 raiseSignal sig = throwErrnoIfMinus1_ "raiseSignal" (c_raise sig)
 
+-- See also note in GHC's rts/RtsUtils.c
+-- This is somewhat fragile because we need to keep the
+-- `#if`-conditional in sync with GHC's runtime.
 #if (defined(openbsd_HOST_OS) || defined(freebsd_HOST_OS) || defined(dragonfly_HOST_OS) || defined(netbsd_HOST_OS) || defined(darwin_HOST_OS))
 foreign import ccall unsafe "genericRaise"
   c_raise :: CInt -> IO CInt