diff -r fbc33813265b -r 2bf1da3c411e src/map.c
--- a/src/map.c	Thu Jun 21 16:00:37 2018 +0200
+++ b/src/map.c	Thu Jun 21 16:10:19 2018 +0200
@@ -154,7 +154,7 @@
     UcxAllocator *allocator = map->allocator;
     
     if (key.hash == 0) {
-        key.hash = ucx_hash(key.data, key.len);
+        key.hash = ucx_hash((const char*)key.data, key.len);
     }
     
     struct UcxMapKey mapkey;
@@ -203,7 +203,7 @@
 
 static void* ucx_map_get_and_remove(UcxMap *map, UcxKey key, int remove) {
     if(key.hash == 0) {
-        key.hash = ucx_hash((char*)key.data, key.len);
+        key.hash = ucx_hash((const char*)key.data, key.len);
     }
     
     size_t slot = key.hash%map->size;
@@ -247,7 +247,7 @@
     UcxKey key;
     key.data = data;
     key.len = len;
-    key.hash = ucx_hash(data, len);
+    key.hash = ucx_hash((const char*)data, len);
     return key;
 }