diff --git a/lib/utils/pyexec.c b/lib/utils/pyexec.c
index ed424a2f95..b398d72661 100644
--- a/lib/utils/pyexec.c
+++ b/lib/utils/pyexec.c
@@ -120,7 +120,9 @@ STATIC int parse_compile_execute(void *source, mp_parse_input_kind_t input_kind,
         {
             size_t n_pool, n_qstr, n_str_data_bytes, n_total_bytes;
             qstr_pool_info(&n_pool, &n_qstr, &n_str_data_bytes, &n_total_bytes);
-            printf("qstr:\n  n_pool=" UINT_FMT "\n  n_qstr=" UINT_FMT "\n  n_str_data_bytes=" UINT_FMT "\n  n_total_bytes=" UINT_FMT "\n", n_pool, n_qstr, n_str_data_bytes, n_total_bytes);
+            printf("qstr:\n  n_pool=" UINT_FMT "\n  n_qstr=" UINT_FMT "\n  "
+                   "n_str_data_bytes=" UINT_FMT "\n  n_total_bytes=" UINT_FMT "\n",
+                   (unsigned)n_pool, (unsigned)n_qstr, (unsigned)n_str_data_bytes, (unsigned)n_total_bytes);
         }
 
         #if MICROPY_ENABLE_GC