diff --git a/src/libstore/misc.cc b/src/libstore/misc.cc
index 5758c3d93..b28768459 100644
--- a/src/libstore/misc.cc
+++ b/src/libstore/misc.cc
@@ -319,7 +319,7 @@ OutputPathMap resolveDerivedPath(Store & store, const DerivedPath::Built & bfd,
         [&](const OutputsSpec::Names & names) {
             return static_cast<std::set<std::string>>(names);
         },
-    }, bfd.outputs);
+    }, bfd.outputs.raw());
     for (auto & output : outputNames) {
         auto outputHash = get(outputHashes, output);
         if (!outputHash)