Add APR_ALLOCATOR_MAX_FREE_DEFAULT override to make APR pools call free(3).
Index: include/apr_allocator.h
--- include/apr_allocator.h.orig
+++ include/apr_allocator.h
@@ -65,6 +65,9 @@ struct apr_memnode_t {
 
 /** Symbolic constants */
 #define APR_ALLOCATOR_MAX_FREE_UNLIMITED 0
+#ifndef APR_ALLOCATOR_MAX_FREE_DEFAULT
+#define APR_ALLOCATOR_MAX_FREE_DEFAULT APR_ALLOCATOR_MAX_FREE_UNLIMITED
+#endif
 
 /**
  * Create a new allocator