diff --git a/file.c b/file.c
index 89867d13c4..88305bd9bd 100644
--- a/file.c
+++ b/file.c
@@ -1253,7 +1253,7 @@ statx_birthtime(const struct statx *stx, VALUE fname)
         /* birthtime is not supported on the filesystem */
         statx_notimplement("birthtime");
     }
-    return rb_time_nano_new(stx->stx_btime.tv_sec, stx->stx_btime.tv_nsec);
+    return rb_time_nano_new((time_t)stx->stx_btime.tv_sec, stx->stx_btime.tv_nsec);
 }
 
 typedef struct statx statx_data;