diff --git a/include/fmt/format.h b/include/fmt/format.h
index 065aa496..d7bb9b0a 100644
--- a/include/fmt/format.h
+++ b/include/fmt/format.h
@@ -759,7 +759,7 @@ using is_fast_float = bool_constant<std::numeric_limits<T>::is_iec559 &&
 template <typename T>
 template <typename U>
 void buffer<T>::append(const U* begin, const U* end) {
-  do {
+  while (begin != end) {
     auto count = to_unsigned(end - begin);
     try_reserve(size_ + count);
     auto free_cap = capacity_ - size_;
@@ -767,7 +767,7 @@ void buffer<T>::append(const U* begin, const U* end) {
     std::uninitialized_copy_n(begin, count, make_checked(ptr_ + size_, count));
     size_ += count;
     begin += count;
-  } while (begin != end);
+  }
 }
 
 template <typename OutputIt, typename T, typename Traits>