diff --git a/src/libutil/file-descriptor.hh b/src/libutil/file-descriptor.hh
index 492b67d74..be61375f6 100644
--- a/src/libutil/file-descriptor.hh
+++ b/src/libutil/file-descriptor.hh
@@ -157,7 +157,7 @@ void closeOnExec(Descriptor fd);
 #endif
 
 #if defined(_WIN32) && _WIN32_WINNT >= 0x0600
-namespace windows (
+namespace windows {
 
 Path handleToPath(Descriptor handle);
 std::wstring handleToFileName(Descriptor handle);