diff --git a/src/util/DynamicFifoBuffer.hxx b/src/util/DynamicFifoBuffer.hxx
index deba848a7..422b35eec 100644
--- a/src/util/DynamicFifoBuffer.hxx
+++ b/src/util/DynamicFifoBuffer.hxx
@@ -45,6 +45,12 @@ public:
 	using typename ForeignFifoBuffer<T>::const_pointer_type;
 	using typename ForeignFifoBuffer<T>::Range;
 
+	/**
+	 * Construct without allocating a buffer.
+	 */
+	explicit constexpr DynamicFifoBuffer(std::nullptr_t n) noexcept
+		:ForeignFifoBuffer<T>(n) {}
+
 	/**
 	 * Allocate a buffer with the given capacity.
 	 */