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(cherry picked from commit 9723f533d85133fa3c4d9421a58c7765cb61e733)
Change-Id: Idd729febc0bb8c7c8db72a0fae73b680f66767f4

src/libexpr/eval.hh

@@ -227,6 +227,7 @@ public:
     template<class T, typename... Args>
     [[nodiscard, gnu::noinline]]
     EvalErrorBuilder<T> & error(const Args & ... args) {
+        // `EvalErrorBuilder::debugThrow` performs the corresponding `delete`.
         return *new EvalErrorBuilder<T>(*this, args...);
     }