From d1f37e66eb78831db7ad9329465640eb3c08b07c Mon Sep 17 00:00:00 2001
From: Alexander Boettcher <alexander.boettcher@genode-labs.com>
Date: Thu, 4 Apr 2019 14:17:36 +0200
Subject: [PATCH] base: fix _sum_in_range in avl structure

Handles corner case when addr + size becomes exactly 0. Before the commit
the function returned that sum is not part of the range, which is wrong.

Issue #3111
---
 repos/base/include/base/allocator_avl.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/repos/base/include/base/allocator_avl.h b/repos/base/include/base/allocator_avl.h
index 0716f3bd1c..41cf9df80f 100644
--- a/repos/base/include/base/allocator_avl.h
+++ b/repos/base/include/base/allocator_avl.h
@@ -48,7 +48,7 @@ class Genode::Allocator_avl_base : public Range_allocator
 	private:
 
 		static bool _sum_in_range(addr_t addr, addr_t offset) {
-			return (~0UL - addr > offset); }
+			return (addr + offset - 1) >= addr; }
 
 		/*
 		 * Noncopyable