diff --git a/src/common/defs.h b/src/common/defs.h
index 6eedee3..4bd0de7 100644
--- a/src/common/defs.h
+++ b/src/common/defs.h
@@ -11,6 +11,8 @@
 // Assuming child type has a field for the base type
 // So for structs it is usually actual downcast, but for unions it is an upcast
 #define DOWNCAST(contype, basename, ptr) containerof(ptr, contype, as_##basename)
+// Expects ptr to be of type srctype* or void*, returns (dsttype*)ptr
+#define EXPECT_AND_CAST(dsttype, srctype, ptr) (((union { typeof(srctype) *src; typeof(dsttype) *dst; }){.src = (ptr)}).dst)
 #define T_ALLOC(count, T) ((T*)calloc((count), sizeof(T)))
 #define HEADER_FN __attribute__((unused)) inline static
 
diff --git a/src/common/util/hash_table.h b/src/common/util/hash_table.h
index cc8ae50..1472b9d 100644
--- a/src/common/util/hash_table.h
+++ b/src/common/util/hash_table.h
@@ -61,9 +61,9 @@ hash_table_delete_by_key_impl(HashTableDynamicData * dyndata, const HashTableKey
 	return hash_table_delete_at_index_impl(dyndata, hash_table_find_impl(dyndata, key));
 }
 
-#define hash_table_init(ht, value_deinit) hash_table_init_impl(&(ht)->as_HashTableDynamicData, sizeof(*(ht)->value_array), IMPLICIT_CAST(void(void*), void(typeof((ht)->value_array)), value_deinit))
+#define hash_table_init(ht, value_deinit) hash_table_init_impl(&(ht)->as_HashTableDynamicData, sizeof(*(ht)->value_array), EXPECT_AND_CAST(void(void*), void(typeof((ht)->value_array)), value_deinit))
 #define hash_table_deinit(ht) hash_table_deinit_impl(&(ht)->as_HashTableDynamicData)
-#define hash_table_insert(ht, key, value_ptr) hash_table_insert_impl(&(ht)->as_HashTableDynamicData, key, IMPLICIT_CAST(const void, const typeof(*(ht)->value_array), value_ptr))
+#define hash_table_insert(ht, key, value_ptr) hash_table_insert_impl(&(ht)->as_HashTableDynamicData, key, EXPECT_AND_CAST(const void, const typeof(*(ht)->value_array), value_ptr))
 #define hash_table_find(ht, key) hash_table_find_impl(&(ht)->as_HashTableDynamicData, key)
 #define hash_table_delete_at_index(ht, index) hash_table_delete_at_index_impl(&(ht)->as_HashTableDynamicData, index)
 #define hash_table_delete_by_key(ht, key) hash_table_delete_by_key_impl(&(ht)->as_HashTableDynamicData, key)