From 6d35e970b7175f6d52b22a325781b66f460416cb Mon Sep 17 00:00:00 2001
From: Massimo Valentini <mvalentini@src.gnome.org>
Date: Fri, 8 Aug 2014 12:37:11 +0200
Subject: [PATCH] ptr difference

---
 src/cairo-polygon-intersect.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/src/cairo-polygon-intersect.c b/src/cairo-polygon-intersect.c
index 701f414..e3cd5eb 100644
--- a/src/cairo-polygon-intersect.c
+++ b/src/cairo-polygon-intersect.c
@@ -800,6 +800,18 @@ cairo_bo_event_compare (const cairo_bo_event_t *a,
     if (cmp)
 	return cmp;
 
+    cmp = a - b;
+
+    if (cmp * (a < b ? -1 : 1) < 0) {
+	intptr_t pa = (intptr_t) a;
+	intptr_t pb = (intptr_t) b;
+
+	fprintf (stderr, "> %16p %16p intptr_t diff: %016lx %8ld int diff: %08x %12d a < b %+d\n",
+		 a, b,
+		 pa - pb, pa - pb,
+		 cmp, cmp, (a < b ? -1 : 1));
+    }
+
     return a - b;
 }
 
-- 
1.9.3