[PATCH v2 8/7] unpack-trees: document that pointer ce can be NULL

["René Scharfe" <rene.scharfe@lsrfire.ath.cx>]

From: Felipe Contreras <felipe.contreras@gmail.com>

If someone adds code that dereferences ce before it is freed without
checking for NULL it will crash sometimes.  Spare that person from
having to wonder about the reason.

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
---
Signoff from http://article.gmane.org/gmane.comp.version-control.git/225972.
No signoff from me because I don't see the point of adding a check for
a developer that probably won't appear.

 unpack-trees.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/unpack-trees.c b/unpack-trees.c
index 57b4074..f22bd89 100644
--- a/unpack-trees.c
+++ b/unpack-trees.c
@@ -605,7 +605,7 @@ static int unpack_nondirectories(int n, unsigned long mask,
 					o);
 		for (i = 0; i < n; i++) {
 			struct cache_entry *ce = src[i + o->merge];
-			if (ce != o->df_conflict_entry)
+			if (ce && ce != o->df_conflict_entry)
 				free(ce);
 		}
 		return rc;
-- 
1.8.3