* Store Value nodes outside of attribute sets. I.e., Attr now stores

  a pointer to a Value, rather than the Value directly.  This improves
  the effectiveness of garbage collection a lot: if the Value is
  stored inside the set directly, then any live pointer to the Value
  causes all other attributes in the set to be live as well.

1 files changed, 1 insertions, 0 deletions

diff --git a/src/libexpr/nixexpr.hh b/src/libexpr/nixexpr.hh
index 1d03220f644a..5c0071dca2ce 100644
--- a/src/libexpr/nixexpr.hh
+++ b/src/libexpr/nixexpr.hh
@@ -137,6 +137,7 @@ struct ExprAttrs : Expr
     Attrs attrs;
     list<Inherited> inherited;
     std::map<Symbol, Pos> attrNames; // used during parsing
+    std::map<Symbol, unsigned int> displs;
     ExprAttrs() : recursive(false) { };
     COMMON_METHODS
 };