Shut up some warnings

(cherry picked from commit 99e8e58f2de9941353b47ed14fbe4ed76d635519)

2 files changed, 4 insertions, 0 deletions

diff --git a/src/libstore/download.hh b/src/libstore/download.hh
index c68381846..68565bf46 100644
--- a/src/libstore/download.hh
+++ b/src/libstore/download.hh
@@ -91,6 +91,8 @@ class Store;
 
 struct Downloader
 {
+    virtual ~Downloader() { }
+
     /* Enqueue a download request, returning a future to the result of
        the download. The future may throw a DownloadError
        exception. */
diff --git a/src/libstore/fs-accessor.hh b/src/libstore/fs-accessor.hh
index f703e1d15..64780a6da 100644
--- a/src/libstore/fs-accessor.hh
+++ b/src/libstore/fs-accessor.hh
@@ -19,6 +19,8 @@ public:
         uint64_t narOffset = 0; // regular files only
     };
 
+    virtual ~FSAccessor() { }
+
     virtual Stat stat(const Path & path) = 0;
 
     virtual StringSet readDirectory(const Path & path) = 0;