3 files changed, 10 insertions, 0 deletions
diff --git a/third_party/nix/src/libexpr/eval.cc b/third_party/nix/src/libexpr/eval.cc
index 2b825bfd2788..0f3b7fabe029 100644
--- a/third_party/nix/src/libexpr/eval.cc
+++ b/third_party/nix/src/libexpr/eval.cc
@@ -5,10 +5,13 @@
 #include <cstring>
 #include <fstream>
 #include <iostream>
+#include <memory>
 #include <new>
 #include <optional>
 #include <variant>
 
+#define GC_INCLUDE_NEW
+
 #include <absl/strings/match.h>
 #include <gc/gc.h>
 #include <gc/gc_cpp.h>
@@ -40,6 +43,10 @@ static char* dupString(const char* s) {
   return t;
 }
 
+std::shared_ptr<Value*> allocRootValue(Value* v) {
+  return std::allocate_shared<Value*>(traceable_allocator<Value*>(), v);
+}
+
 static void printValue(std::ostream& str, std::set<const Value*>& active,
                        const Value& v) {
   checkInterrupt();
diff --git a/third_party/nix/src/libexpr/nixexpr.hh b/third_party/nix/src/libexpr/nixexpr.hh
index 4b2bd86ef966..365235377f71 100644
--- a/third_party/nix/src/libexpr/nixexpr.hh
+++ b/third_party/nix/src/libexpr/nixexpr.hh
@@ -3,6 +3,7 @@
 #include <map>
 #include <optional>
 #include <variant>
+
 #include <absl/container/flat_hash_map.h>
 
 #include "libexpr/symbol-table.hh"
diff --git a/third_party/nix/src/libexpr/value.hh b/third_party/nix/src/libexpr/value.hh
index 7308dd31933a..cb1b8796cfe4 100644
--- a/third_party/nix/src/libexpr/value.hh
+++ b/third_party/nix/src/libexpr/value.hh
@@ -247,4 +247,6 @@ typedef std::map<Symbol, Value*, std::less<Symbol>,
                  traceable_allocator<std::pair<const Symbol, Value*>>>
     ValueMap;
 
+std::shared_ptr<Value*> allocRootValue(Value* v);
+
 }  // namespace nix