Change order of evaluation for default parameters

Explicitly given parameters are always evaluated before default parameters.
Aligns with spec and Scala 2.

Author: odersky

compiler/src/dotty/tools/dotc/ast/tpd.scala

@@ -817,8 +817,8 @@ object tpd extends Trees.Instance[Type] with TypedTreeInfo {
       val ownerAcc = new TreeAccumulator[immutable.Set[Symbol]] {
         def apply(ss: immutable.Set[Symbol], tree: Tree)(using Context) = tree match {
           case tree: DefTree =>
-            if (tree.symbol.exists) ss + tree.symbol.owner
-            else ss
+            val sym = tree.symbol
+            if sym.exists && !sym.owner.is(Package) then ss + sym.owner else ss
           case _ =>
             foldOver(ss, tree)
         }

compiler/src/dotty/tools/dotc/typer/Applications.scala

@@ -756,7 +756,7 @@ trait Applications extends Compatibility {
       val app1 =
         if (!success) app0.withType(UnspecifiedErrorType)
         else {
-          if (!sameSeq(args, orderedArgs.dropWhile(_ eq EmptyTree)) && !isJavaAnnotConstr(methRef.symbol)) {
+          if !sameSeq(args, orderedArgs) && !isJavaAnnotConstr(methRef.symbol) then
             // need to lift arguments to maintain evaluation order in the
             // presence of argument reorderings.
 
@@ -787,7 +787,7 @@ trait Applications extends Compatibility {
                 argDefBuf.zip(impureArgIndices), (arg, idx) => originalIndex(idx)).map(_._1)
             }
             liftedDefs ++= orderedArgDefs
-          }
+          end if
           if (sameSeq(typedArgs, args)) // trick to cut down on tree copying
             typedArgs = args.asInstanceOf[List[Tree]]
           assignType(app0, normalizedFun, typedArgs)

compiler/test/dotc/pos-test-pickling.blacklist

@@ -60,3 +60,6 @@ i9793.scala
 
 # lazy_implicit symbol has different position after pickling
 i8182.scala
+
+# local lifted value in annotation argument has different position after pickling
+i2797a

tests/run/i11571.check

@@ -0,0 +1,2 @@
+17
+42

tests/run/i11571.scala

@@ -0,0 +1,8 @@
+import util.chaining.scalaUtilChainingOps
+object Test extends App {
+  def x = 42.tap(println(_))
+  def y = 27.tap(println(_))
+  def z = 17.tap(println(_))
+  def f(i: Int = x, j: Int = y) = i + j
+  f(j = z)
+}