From 39109c05be66c7dde854be3021c24183c92bf6bb Mon Sep 17 00:00:00 2001
From: Taeer Bar-Yam <taeer@bar-yam.me>
Date: Fri, 3 Oct 2025 12:49:55 -0400
Subject: [PATCH] libexpr: allocate ExprOpHasAttr's AttrPath in Exprs::alloc

---
 src/libexpr/include/nix/expr/nixexpr.hh | 10 +++++++---
 src/libexpr/parser.y                    |  2 +-
 2 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/src/libexpr/include/nix/expr/nixexpr.hh b/src/libexpr/include/nix/expr/nixexpr.hh
index 512999020..b66dba4f3 100644
--- a/src/libexpr/include/nix/expr/nixexpr.hh
+++ b/src/libexpr/include/nix/expr/nixexpr.hh
@@ -348,10 +348,14 @@ struct ExprSelect : Expr
 struct ExprOpHasAttr : Expr
 {
     Expr * e;
-    AttrPath attrPath;
-    ExprOpHasAttr(Expr * e, AttrPath attrPath)
+    std::span<AttrName> attrPath;
+
+    ExprOpHasAttr(std::pmr::polymorphic_allocator<char> alloc, Expr * e, std::vector<AttrName> attrPath)
         : e(e)
-        , attrPath(std::move(attrPath)) {};
+        , attrPath({alloc.allocate_object<AttrName>(attrPath.size()), attrPath.size()})
+    {
+        std::ranges::copy(attrPath, this->attrPath.begin());
+    };
 
     PosIdx getPos() const override
     {
diff --git a/src/libexpr/parser.y b/src/libexpr/parser.y
index 56e65acfb..9186fcf4b 100644
--- a/src/libexpr/parser.y
+++ b/src/libexpr/parser.y
@@ -261,7 +261,7 @@ expr_op
   | expr_op OR expr_op { $$ = new ExprOpOr(state->at(@2), $1, $3); }
   | expr_op IMPL expr_op { $$ = new ExprOpImpl(state->at(@2), $1, $3); }
   | expr_op UPDATE expr_op { $$ = new ExprOpUpdate(state->at(@2), $1, $3); }
-  | expr_op '?' attrpath { $$ = new ExprOpHasAttr($1, std::move(*$3)); delete $3; }
+  | expr_op '?' attrpath { $$ = new ExprOpHasAttr(state->alloc, $1, std::move(*$3)); delete $3; }
   | expr_op '+' expr_op
     { $$ = new ExprConcatStrings(state->at(@2), false, new std::vector<std::pair<PosIdx, Expr *> >({{state->at(@1), $1}, {state->at(@3), $3}})); }
   | expr_op '-' expr_op { $$ = new ExprCall(state->at(@2), new ExprVar(state->s.sub), {$1, $3}); }