* In an nested with' where the inner with is a variable (with ...;

with someVar; ...'), the contents of the variable would be
  clobbered.  (The attributes in the outer `with' were added to the
  variable.)

src/nix-env/nix-env.cc

@@ -1089,6 +1089,7 @@ static void opQuery(Globals & globals,
     
     foreach (vector<DrvInfo>::iterator, i, elems2) {
         try {
+            startNest(nest, lvlDebug, format("outputting query result `%1%'") % i->attrPath);
 
             /* For table output. */
             Strings columns;