diff --git a/src/basic/alloc-util.h b/src/basic/alloc-util.h
index 65d5175619..57f1b186ee 100644
--- a/src/basic/alloc-util.h
+++ b/src/basic/alloc-util.h
@@ -13,6 +13,7 @@
 #endif
 
 typedef void (*free_func_t)(void *p);
+typedef void* (*mfree_func_t)(void *p);
 
 /* If for some reason more than 4M are allocated on the stack, let's abort immediately. It's better than
  * proceeding and smashing the stack limits. Note that by default RLIMIT_STACK is 8M on Linux. */