Index: Objects/object.c
===================================================================
--- Objects/object.c	(révision 69444)
+++ Objects/object.c	(copie de travail)
@@ -1073,7 +1073,22 @@
 _Py_HashPointer(void *p)
 {
 #if SIZEOF_LONG >= SIZEOF_VOID_P
-	return (long)p;
+	unsigned long x = (unsigned long)p;
+	/* bottom 3 bits are likely to be 0; rotate them to the top to avoid
+	   excessive hash collisions for dicts and sets */
+	x = (x >> 4) + (x & 15);
+	if (x == -1)
+		x = -2;
+	return x;
+/* 64-bit Windows has sizeof(long) == 4 and sizeof(void *) == 8 */
+#elif SIZEOF_VOID_P == SIZEOF_LONG*2
+	unsigned long x;
+	size_t y = (size_t)p;
+	y = (y >> 4) + (y & 15);
+	x = (unsigned long)y + (unsigned long)(y >> 8*SIZEOF_LONG);
+	if (x == -1)
+		x = -2;
+	return x;
 #else
 	/* convert to a Python long and hash that */
 	PyObject* longobj;