diff --git a/gc.c b/gc.c
index 5d0c342206..2bfff21004 100644
--- a/gc.c
+++ b/gc.c
@@ -10905,8 +10905,16 @@ ruby_xrealloc2_body(void *ptr, size_t n, size_t size)
 void
 ruby_sized_xfree(void *x, size_t size)
 {
-    if (x) {
-	objspace_xfree(&rb_objspace, x, size);
+    if (LIKELY(x)) {
+        /* It's possible for a C extension's pthread destructor function set by pthread_key_create
+         * to be called after ruby_vm_destruct and attempt to free memory. Fall back to mimfree in
+         * that case. */
+        if (LIKELY(GET_VM())) {
+            objspace_xfree(&rb_objspace, x, size);
+        }
+        else {
+            ruby_mimfree(x);
+        }
     }
 }