diff --git a/src/lib/zlib/GzipOutputStream.cxx b/src/lib/zlib/GzipOutputStream.cxx
index 19ae7c694..21276ee15 100644
--- a/src/lib/zlib/GzipOutputStream.cxx
+++ b/src/lib/zlib/GzipOutputStream.cxx
@@ -23,7 +23,7 @@ GzipOutputStream::GzipOutputStream(OutputStream &_next)
 		throw ZlibError(result);
 }
 
-GzipOutputStream::~GzipOutputStream()
+GzipOutputStream::~GzipOutputStream() noexcept
 {
 	deflateEnd(&z);
 }
diff --git a/src/lib/zlib/GzipOutputStream.hxx b/src/lib/zlib/GzipOutputStream.hxx
index 8f9ecfc82..e50f92232 100644
--- a/src/lib/zlib/GzipOutputStream.hxx
+++ b/src/lib/zlib/GzipOutputStream.hxx
@@ -26,7 +26,7 @@ public:
 	 * Throws #ZlibError on error.
 	 */
 	explicit GzipOutputStream(OutputStream &_next);
-	~GzipOutputStream();
+	~GzipOutputStream() noexcept;
 
 	/**
 	 * Throws on error.