From dbfe6318b3a38294c27546a1d454767092f5346e Mon Sep 17 00:00:00 2001
From: Taeer Bar-Yam <taeer@bar-yam.me>
Date: Sun, 23 Nov 2025 00:05:34 +0100
Subject: [PATCH] libexpr: move ExprCall storage to the arena

---
 src/libexpr/nixexpr.cc | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/libexpr/nixexpr.cc b/src/libexpr/nixexpr.cc
index 34d286f4e..37e22c466 100644
--- a/src/libexpr/nixexpr.cc
+++ b/src/libexpr/nixexpr.cc
@@ -486,6 +486,12 @@ void ExprLambda::bindVars(EvalState & es, const std::shared_ptr<const StaticEnv>
 
 void ExprCall::bindVars(EvalState & es, const std::shared_ptr<const StaticEnv> & env)
 {
+    // Move storage into the Exprs arena
+    {
+        auto arena = es.mem.exprs.alloc;
+        std::pmr::vector<Expr *> newArgs{std::move(*args), arena};
+        args.emplace(std::move(newArgs), arena);
+    }
     if (es.debugRepl)
         es.exprEnvs.insert(std::make_pair(this, env));