[libgsf] Avoid (unlikely) NULL pointer dereference

[J.H.M. Dassen (Ray) <jdassen src gnome org>]

commit 01793f3c5bbb88f78d510762652b9343ebdf04d7
Author: J.H.M. Dassen (Ray) <jdassen debian org>
Date:   Sat Jan 5 20:36:57 2013 +0100

    Avoid (unlikely) NULL pointer dereference

 gsf/gsf-shared-memory.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
---
diff --git a/gsf/gsf-shared-memory.c b/gsf/gsf-shared-memory.c
index 9492f8c..c098019 100644
--- a/gsf/gsf-shared-memory.c
+++ b/gsf/gsf-shared-memory.c
@@ -59,6 +59,7 @@ gsf_shared_memory_mmapped_new (void *buf, gsf_off_t size)
 		return NULL;
 	} else {
 		GsfSharedMemory *mem = gsf_shared_memory_new (buf, size, FALSE);
+		if (G_UNLIKELY (NULL == mem)) return NULL;
 		mem->needs_unmap = TRUE;
 		return mem;
 	}