diff --git a/librpc/ndr/libndr.h b/librpc/ndr/libndr.h
index 2a80ba5df0a..568f7827184 100644
--- a/librpc/ndr/libndr.h
+++ b/librpc/ndr/libndr.h
@@ -476,13 +476,13 @@ enum ndr_compression_alg {
 #define NDR_PULL_ALLOC_N(ndr, s, n) do { \
 	_NDR_PULL_FIX_CURRENT_MEM_CTX(ndr);\
 	(s) = talloc_array_ptrtype(ndr->current_mem_ctx, (s), n); \
-	if (unlikely(!(s))) return ndr_pull_error(ndr, NDR_ERR_ALLOC, "Alloc %u * %s failed: %s\n", (unsigned)n, # s, __location__); \
+	if (unlikely(!(s))) return ndr_pull_error(ndr, NDR_ERR_ALLOC, "Alloc %zu * %s failed: %s\n", (size_t)n, # s, __location__); \
 } while (0)
 
 
 #define NDR_PUSH_ALLOC_SIZE(ndr, s, size) do { \
        (s) = talloc_array(ndr, uint8_t, size); \
-       if (unlikely(!(s))) return ndr_push_error(ndr, NDR_ERR_ALLOC, "push alloc %u failed: %s\n", (unsigned)size, __location__); \
+       if (unlikely(!(s))) return ndr_push_error(ndr, NDR_ERR_ALLOC, "push alloc %zu failed: %s\n", (size_t)size, __location__); \
 } while (0)
 
 #define NDR_PUSH_ALLOC(ndr, s) do { \