@@ -, +, @@ 
 src/data/memory_chunk.cc          |    2 +-
 src/torrent/data/block.h          |    1 +
 src/torrent/data/block_transfer.h |    1 +
 3 files changed, 3 insertions(+), 1 deletions(-)
--- a/src/data/memory_chunk.cc	
+++ a/src/data/memory_chunk.cc	
@@ -71,7 +71,7 @@ MemoryChunk::MemoryChunk(char* ptr, char* begin, char* end, int prot, int flags)
   if (page_align() >= m_pagesize)
     throw internal_error("MemoryChunk::MemoryChunk(...) received an page alignment >= page size");
 
-  if ((ptrdiff_t)ptr % m_pagesize)
+  if ((std::ptrdiff_t)ptr % m_pagesize)
     throw internal_error("MemoryChunk::MemoryChunk(...) is not aligned to a page");
 }
 
--- a/src/torrent/data/block.h	
+++ a/src/torrent/data/block.h	
@@ -37,6 +37,7 @@ 
 #ifndef LIBTORRENT_BLOCK_H
 #define LIBTORRENT_BLOCK_H
 
+#include <cstddef>
 #include <vector>
 #include <torrent/common.h>
 #include <torrent/data/block_transfer.h>
--- a/src/torrent/data/block_transfer.h	
+++ a/src/torrent/data/block_transfer.h	
@@ -37,6 +37,7 @@ 
 #ifndef LIBTORRENT_BLOCK_TRANSFER_H
 #define LIBTORRENT_BLOCK_TRANSFER_H
 
+#include <cstddef>
 #include <torrent/common.h>
 #include <torrent/data/piece.h>