diff --git a/src/cache/cache.c b/src/cache/cache.c
index 50e460fe5..63a7e24b8 100644
--- a/src/cache/cache.c
+++ b/src/cache/cache.c
@@ -298,7 +298,7 @@ enlarge_entry(struct cache_entry *cached, off_t size)
 static struct fragment *
 frag_alloc(size_t size)
 {
-	struct fragment *f = mem_mmap_alloc(FRAGSIZE(size));
+	struct fragment *f = (struct fragment *)mem_mmap_alloc(FRAGSIZE(size));
 
 	if (!f) return NULL;
 	memset(f, 0, FRAGSIZE(size));
@@ -308,7 +308,7 @@ frag_alloc(size_t size)
 static struct fragment *
 frag_realloc(struct fragment *f, size_t size)
 {
-	return mem_mmap_realloc(f, FRAGSIZE(f->real_length), FRAGSIZE(size));
+	return (struct fragment *)mem_mmap_realloc(f, FRAGSIZE(f->real_length), FRAGSIZE(size));
 }
 
 static void
diff --git a/src/protocol/bittorrent/piececache.c b/src/protocol/bittorrent/piececache.c
index 96fa2adec..e4385e23d 100644
--- a/src/protocol/bittorrent/piececache.c
+++ b/src/protocol/bittorrent/piececache.c
@@ -713,7 +713,7 @@ bittorrent_file_piece_translation(struct bittorrent_meta *meta,
 	if (trans == BITTORRENT_READ) {
 		assert(!entry->data);
 
-		entry->data = mem_mmap_alloc(piece_length);
+		entry->data = (char *)mem_mmap_alloc(piece_length);
 		if (!entry->data)
 			return BITTORRENT_STATE_OUT_OF_MEM;
 	}
@@ -904,7 +904,7 @@ add_to_bittorrent_piece_cache(struct bittorrent_peer_connection *peer,
 
 	piece_length = get_bittorrent_piece_length(meta, piece);
 	if (!entry->data) {
-		entry->data = mem_mmap_alloc(piece_length);
+		entry->data = (char *)mem_mmap_alloc(piece_length);
 		if (!entry->data) {
 			add_request_to_bittorrent_piece_cache(peer->bittorrent, request);
 			return BITTORRENT_STATE_OK;