[commit: ghc] master: Linker: Fix type in m32_free_internal (8ddf417)

[git at git.haskell.org]

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

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/8ddf41744ea8b0c1d034f9c5e062b0112d3d3aff/ghc

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

commit 8ddf41744ea8b0c1d034f9c5e062b0112d3d3aff
Author: Erik de Castro Lopo <erikd at mega-nerd.com>
Date:   Fri Oct 30 15:07:21 2015 +1100

    Linker: Fix type in m32_free_internal
    
    The code:
    
        uint64_t c = __sync_sub_and_fetch((uint64_t*)addr, 1);
    
    was causing GCC to emit atomic instructions for 64 bit values which
    are not available on PowerPC. However, since PowerPC only has a 32
    bit address space, use of a 64 bit value is superflous.
    
    Switching the type from `uint64_t` to `uintptr_t` should simply do
    the correct thing on all 32 and 64 bit architectures.
    
    Reviewers: austin, bgamari, simonmar
    
    Subscribers: thomie
    
    Differential Revision: https://phabricator.haskell.org/D1399
    
    GHC Trac Issues: #11036


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8ddf41744ea8b0c1d034f9c5e062b0112d3d3aff
 rts/Linker.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/rts/Linker.c b/rts/Linker.c
index 98969b9..e7bb8f0 100644
--- a/rts/Linker.c
+++ b/rts/Linker.c
@@ -1217,7 +1217,7 @@ static void m32_allocator_init(m32_allocator m32) {
  * You shouldn't have to use this method. Use `m32_free` instead.
  */
 static void m32_free_internal(void * addr) {
-   uint64_t c = __sync_sub_and_fetch((uint64_t*)addr, 1);
+   uintptr_t c = __sync_sub_and_fetch((uintptr_t*)addr, 1);
    if (c == 0) {
       munmapForLinker(addr, getPageSize());
    }