Postpone tree compaction till all phases finish operating TASTY.

Linker adds new sections. Wait for sections to be added and then compact.

Author: DarkDimius

src/dotty/tools/dotc/core/tasty/TastyPickler.scala

@@ -13,13 +13,13 @@ import ast.tpd
 class TastyPickler {
 
   private val sections = new mutable.ArrayBuffer[(TastyName.NameRef, TastyBuffer)]
+  val uuid = UUID.randomUUID()
 
   private val headerBuffer = {
     val buf = new TastyBuffer(24)
     for (ch <- header) buf.writeByte(ch.toByte)
     buf.writeNat(MajorVersion)
     buf.writeNat(MinorVersion)
-    val uuid = UUID.randomUUID()
     buf.writeUncompressedLong(uuid.getMostSignificantBits)
     buf.writeUncompressedLong(uuid.getLeastSignificantBits)
     buf
@@ -31,6 +31,7 @@ class TastyPickler {
     sections += ((nameBuffer.nameIndex(name), buf))
 
   def assembleParts(): Array[Byte] = {
+    treePkl.compactify()
     def lengthWithLength(buf: TastyBuffer) = {
       buf.assemble()
       buf.length + natSize(buf.length)

src/dotty/tools/dotc/core/tasty/TreePickler.scala

@@ -541,12 +541,17 @@ class TreePickler(pickler: TastyPickler) {
   }
 
   def pickle(trees: List[Tree])(implicit ctx: Context) = {
+    trees.foreach(tree => if (!tree.isEmpty) pickleTree(tree))
+    assert(forwardSymRefs.isEmpty, i"unresolved symbols: ${forwardSymRefs.keySet.toList}%, %")
+  }
+
+  def compactify() = {
+    buf.compactify()
+    assert(forwardSymRefs.isEmpty, s"unresolved symbols: ${forwardSymRefs.keySet.toList}%, %")
+
     def updateMapWithDeltas[T](mp: collection.mutable.Map[T, Addr]) =
       for (key <- mp.keysIterator.toBuffer[T]) mp(key) = adjusted(mp(key))
 
-    trees.foreach(tree => if (!tree.isEmpty) pickleTree(tree))
-    assert(forwardSymRefs.isEmpty, i"unresolved symbols: ${forwardSymRefs.keySet.toList}%, %")
-    compactify()
     updateMapWithDeltas(symRefs)
   }
 }