1 files changed, 1 insertions, 1 deletions
diff --git a/zix/hash.h b/zix/hash.h
index 9546a64..2550676 100644
--- a/zix/hash.h
+++ b/zix/hash.h
@@ -73,7 +73,7 @@ zix_hash_free(ZixHash* hash);
 /**
    Return the number of elements in `hash`.
 */
-ZIX_API size_t
+ZIX_PURE_API size_t
 zix_hash_size(const ZixHash* hash);
 
 /**