SI-7501 Pickler: owner adjustment for param syms in annotation args

Pickling of trees within annotation arguments led to an unfortunate
situation: the MethodType of a symbol contained a value parameter
symbol that was pickled as though it were owned by the enclosing
class (the root symbol of the pickle.)

Under separate compilation, this would appear as a member of that
class.

Anyone using `@deprecatedName('oldName)` was exposed to this problem,
as the argument expands to `Symbol.apply("oldName")`.

This commit extends some similar treatment of local type parameters
to also consider value parameters.

1 files changed, 6 insertions, 1 deletions

diff --git a/src/compiler/scala/tools/nsc/symtab/classfile/Pickler.scala b/src/compiler/scala/tools/nsc/symtab/classfile/Pickler.scala
index 9bad29097c..9ac1ce1b9c 100644
--- a/src/compiler/scala/tools/nsc/symtab/classfile/Pickler.scala
+++ b/src/compiler/scala/tools/nsc/symtab/classfile/Pickler.scala
@@ -88,12 +88,17 @@ abstract class Pickler extends SubComponent {
     /** Returns usually symbol's owner, but picks classfile root instead
      *  for existentially bound variables that have a non-local owner.
      *  Question: Should this be done for refinement class symbols as well?
+     *
+     *  Note: tree pickling also finds its way here; e.g. in SI-7501 the pickling
+     *  of trees in annotation arguments considers the parameter symbol of a method
+     *  called in such a tree as "local". The condition `sym.isValueParameter` was
+     *  added to fix that bug, but there may be a better way.
      */
     private def localizedOwner(sym: Symbol) =
       if (isLocal(sym) && !isRootSym(sym) && !isLocal(sym.owner))
         // don't use a class as the localized owner for type parameters that are not owned by a class: those are not instantiated by asSeenFrom
         // however, they would suddenly be considered by asSeenFrom if their localized owner became a class (causing the crashes of #4079, #2741)
-        (if(sym.isTypeParameter && !sym.owner.isClass) nonClassRoot
+        (if ((sym.isTypeParameter || sym.isValueParameter) && !sym.owner.isClass) nonClassRoot
          else root)
       else sym.owner