Cache ictx.settings.Yscala2Stdlib.value

Author: nicolasstucki

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

@@ -19,6 +19,7 @@ import printing.Formatting.hl
 import config.Printers
 
 import scala.annotation.internal.sharable
+import scala.annotation.threadUnsafe
 
 object desugar {
   import untpd._
@@ -440,6 +441,8 @@ object desugar {
 
   /** The expansion of a class definition. See inline comments for what is involved */
   def classDef(cdef: TypeDef)(using Context): Tree = {
+    @threadUnsafe lazy val compilingScala2StdLib = ctx.settings.Yscala2Stdlib.value
+
     val impl @ Template(constr0, _, self, _) = cdef.rhs: @unchecked
     val className = normalizeName(cdef, impl).asTypeName
     val parents = impl.parents
@@ -662,9 +665,7 @@ object desugar {
     //       new C[...](p1, ..., pN)(moreParams)
     val (caseClassMeths, enumScaffolding) = {
       def syntheticProperty(name: TermName, tpt: Tree, rhs: Tree) =
-        val mods =
-          if ctx.settings.Yscala2Stdlib.value then synthetic | Inline
-          else synthetic
+        val mods = if compilingScala2StdLib then synthetic | Inline else synthetic
         DefDef(name, Nil, tpt, rhs).withMods(mods)
 
       def productElemMeths =
@@ -778,7 +779,7 @@ object desugar {
           val unapplyParam = makeSyntheticParameter(tpt = classTypeRef)
           val unapplyRHS =
             if (arity == 0) Literal(Constant(true))
-            else if ctx.settings.Yscala2Stdlib.value then scala2LibCompatUnapplyRhs(unapplyParam.name)
+            else if compilingScala2StdLib then scala2LibCompatUnapplyRhs(unapplyParam.name)
             else Ident(unapplyParam.name)
           val unapplyResTp = if (arity == 0) Literal(Constant(true)) else TypeTree()
 

compiler/src/dotty/tools/dotc/transform/PostTyper.scala

@@ -20,6 +20,8 @@ import util.SrcPos
 import reporting._
 import NameKinds.WildcardParamName
 
+import scala.annotation.{constructorOnly, threadUnsafe}
+
 object PostTyper {
   val name: String = "posttyper"
   val description: String = "additional checks and cleanups after type checking"
@@ -78,7 +80,7 @@ class PostTyper extends MacroTransform with InfoTransformer { thisPhase =>
   override def transformPhase(using Context): Phase = thisPhase.next
 
   def newTransformer(using Context): Transformer =
-    new PostTyperTransformer
+    new PostTyperTransformer(ctx)
 
   val superAcc: SuperAccessors = new SuperAccessors(thisPhase)
   val synthMbr: SyntheticMembers = new SyntheticMembers(thisPhase)
@@ -93,7 +95,9 @@ class PostTyper extends MacroTransform with InfoTransformer { thisPhase =>
     // TODO fill in
   }
 
-  class PostTyperTransformer extends Transformer {
+  class PostTyperTransformer(@constructorOnly ictx: Context) extends Transformer {
+
+    @threadUnsafe private val compilingScala2StdLib = ictx.settings.Yscala2Stdlib.value(using ictx)
 
     private var inJavaAnnot: Boolean = false
 
@@ -536,7 +540,7 @@ class PostTyper extends MacroTransform with InfoTransformer { thisPhase =>
 
     private def scala2LibPatch(tree: TypeDef)(using Context) =
       val sym = tree.symbol
-      if ctx.settings.Yscala2Stdlib.value
+      if compilingScala2StdLib
         && sym.is(ModuleClass) && !sym.derivesFrom(defn.SerializableClass)
         && sym.companionClass.derivesFrom(defn.SerializableClass)
       then