diff --git a/Objects/obmalloc.c b/Objects/obmalloc.c
index d230bbdad3c4cf..b05273b09126eb 100644
--- a/Objects/obmalloc.c
+++ b/Objects/obmalloc.c
@@ -2738,7 +2738,8 @@ py_mimalloc_print_stats(FILE *out)
             MI_LARGE_OBJ_SIZE_MAX);
 
     mi_heap_t *heap = mi_heap_get_default();
-    struct _alloc_stats stats = {};
+    struct _alloc_stats stats;
+    memset(&stats, 0, sizeof(stats));
     mi_heap_visit_blocks(heap, false, &_collect_alloc_stats, &stats);
 
     fprintf(out, "    Allocated Blocks: %ld\n", stats.allocated_blocks);
diff --git a/PC/pyconfig.h b/PC/pyconfig.h
index ac20129cd30fcc..e6b368caffe280 100644
--- a/PC/pyconfig.h
+++ b/PC/pyconfig.h
@@ -511,6 +511,9 @@ Py_NO_ENABLE_SHARED to find out.  Also support MS_NO_COREDLL for b/w compat */
 /* Use Python's own small-block memory-allocator. */
 #define WITH_PYMALLOC 1
 
+/* Define if you want to compile in mimalloc memory allocator. */
+#define WITH_MIMALLOC 1
+
 /* Define if you want to compile in object freelists optimization */
 #define WITH_FREELISTS 1