1 files changed, 1 insertions, 1 deletions
diff --git a/src/libstore/http-binary-cache-store.cc b/src/libstore/http-binary-cache-store.cc
index 6fdae40e3603..ab524d523cf2 100644
--- a/src/libstore/http-binary-cache-store.cc
+++ b/src/libstore/http-binary-cache-store.cc
@@ -73,7 +73,7 @@ protected:
         try {
             getDownloader()->download(req);
         } catch (DownloadError & e) {
-            throw UploadToHTTP(format("uploading to HTTP binary cache at %1% not supported: %2%") % cacheUri % e.msg());
+            throw UploadToHTTP("while uploading to HTTP binary cache at '%s': %s", cacheUri, e.msg());
         }
     }