Fix of #50 - volatile

Volatile checking needs to take all intersections into account; previously these
could be discarded through needsChecking.

Plus several refactorings and additions.

1) Module vals now have Final and Stable flags set
2) All logic around isVolatile is now in TypeOps; some of it was moved from Types.
3) Added stability checking to Select and SelectFromType typings.

Todo: We should find a better name for isVolatile. Maybe define the negation instead under the name
"isRealizable"?.

1 files changed, 1 insertions, 1 deletions

diff --git a/src/dotty/tools/dotc/core/SymDenotations.scala b/src/dotty/tools/dotc/core/SymDenotations.scala
index 5fbf6c2c4..b9eb2f945 100644
--- a/src/dotty/tools/dotc/core/SymDenotations.scala
+++ b/src/dotty/tools/dotc/core/SymDenotations.scala
@@ -355,7 +355,7 @@ object SymDenotations {
     final def isStable(implicit ctx: Context) = {
       val isUnstable =
         (this is UnstableValue) ||
-        info.isVolatile && !hasAnnotation(defn.uncheckedStableClass)
+        ctx.isVolatile(info) && !hasAnnotation(defn.uncheckedStableClass)
       (this is Stable) || isType || {
         if (isUnstable) false
         else { setFlag(Stable); true }