[commit: ghc] master: Revert "Paranoid integer overflow check in osGetMBlocks" (c87c19f)

[git at git.haskell.org]

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

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/c87c19f55a3ed7f437d738bfbf436afbc3ac0877/ghc

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commit c87c19f55a3ed7f437d738bfbf436afbc3ac0877
Author: Austin Seipp <aseipp at pobox.com>
Date:   Thu Aug 29 17:30:11 2013 -0500

    Revert "Paranoid integer overflow check in osGetMBlocks"
    
    This reverts commit 1247dff7b852d45dc5006ae8be33ac991cc76c74.
    
    Signed-off-by: Austin Seipp <aseipp at pobox.com>


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

c87c19f55a3ed7f437d738bfbf436afbc3ac0877
 rts/posix/OSMem.c |    3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/rts/posix/OSMem.c b/rts/posix/OSMem.c
index 76b863e..cbc76f8 100644
--- a/rts/posix/OSMem.c
+++ b/rts/posix/OSMem.c
@@ -184,8 +184,7 @@ osGetMBlocks(nat n)
 
   // Compute size = MBLOCK_SIZE * (W_)n,
   // while testing for integer overflow.
-  if (n > (nat)((W_)-1))
-      barf("osGetMBlocks: impossibly large MBlock count %d; nat larger than W_?", n);
+  // We assume that W_ is at least as large a type as nat.
   if ((W_)n > ((W_)-1) / MBLOCK_SIZE) {
       // We tried to allocate, say, 4 GB or more on a 32-bit system.
       errorBelch("out of memory (requested %d MBlocks)", n);