fixed #828, #789

2 files changed, 71 insertions, 2 deletions

diff --git a/src/compiler/scala/tools/nsc/typechecker/RefChecks.scala b/src/compiler/scala/tools/nsc/typechecker/RefChecks.scala
index de1f3f3119..d22ab4942e 100644
--- a/src/compiler/scala/tools/nsc/typechecker/RefChecks.scala
+++ b/src/compiler/scala/tools/nsc/typechecker/RefChecks.scala
@@ -249,8 +249,20 @@ abstract class RefChecks extends InfoTransform {
              else clazz.toString() + " needs to be abstract") + ", since " + msg);
           clazz.setFlag(ABSTRACT)
         }
+        // Find a concrete Java method that overrides `sym' under the erasure model.
+        // Bridge symbols qualify.
+        // Used as a fall back if no overriding symbol of a Java abstract method can be found
+        def javaErasedOverridingSym(sym: Symbol): Symbol =
+          clazz.tpe.findMember(sym.name, PRIVATE, 0, false).filter(other =>
+            !other.isDeferred &&
+            (other hasFlag JAVA) && {
+              val tp1 = erasure.erasure(clazz.thisType.memberType(sym))
+              val tp2 = erasure.erasure(clazz.thisType.memberType(other))
+              atPhase(currentRun.erasurePhase.next)(tp1 matches tp2)
+            })
         for (val member <- clazz.tpe.nonPrivateMembers)
-          if (member.isDeferred && !(clazz hasFlag ABSTRACT)) {
+          if (member.isDeferred && !(clazz hasFlag ABSTRACT) &&
+              !((member hasFlag JAVA) && javaErasedOverridingSym(member) != NoSymbol)) {
             abstractClassError(
               false, infoString(member) + " is not defined" + analyzer.varNotice(member))
           } else if ((member hasFlag ABSOVERRIDE) && member.isIncompleteIn(clazz)) {
@@ -263,6 +275,12 @@ abstract class RefChecks extends InfoTransform {
           }
         // 3. Check that concrete classes do not have deferred definitions
         // that are not implemented in a subclass.
+        // Note that this is not the same as (2); In a situation like
+        //
+        // class C { def m: Int = 0}
+        // class D extends C { def m: Int }
+        //
+        // (3) is violated but not (2).
         def checkNoAbstractDecls(bc: Symbol) {
           for (val decl <- bc.info.decls.elements) {
             if (decl.isDeferred) {
diff --git a/src/library/scala/collection/immutable/Tree.scala b/src/library/scala/collection/immutable/Tree.scala
index 3853e23cd9..99a123273c 100644
--- a/src/library/scala/collection/immutable/Tree.scala
+++ b/src/library/scala/collection/immutable/Tree.scala
@@ -17,7 +17,11 @@
 ** Balanced Trees. These have no storage overhead compared to plain
 ** unbalanced binary trees, and their performance is in general better
 ** than AVL trees.
-*
+**
+** NOTE: This code was until 2007-04-01 under a GPL license. The author has
+** given permission to remove that license, so that now this code is under
+** the general license for the Scala libraries. I include his mail at the
+** bottom of this file for reference.
 */
 
 package scala.collection.immutable
@@ -387,3 +391,50 @@ private case class GBNode[A <% Ordered[A],B](key: A,
   override def hashCode() =
     value.hashCode() + smaller.hashCode() + bigger.hashCode()
 }
+
+/* Here is the e-mail where the Author agreed to the change in license.
+
+from	Erik Stenman <happi.stenman@gmail.com>
+to	martin odersky <martin.odersky@epfl.ch>,
+date	Tue, Apr 29, 2008 at 3:31 PM
+subject	Re: test
+mailed-by	chara.epfl.ch
+signed-by	gmail.com
+
+Hi Martin,
+
+I am fine with that change, and since I don't have a scala distribution handy,
+I am also fine with you doing the change yourself. Is that OK?
+
+Sorry for my dead home address, I'll add an English response to it at some time.
+
+I am doing fine, and my family is also doing fine.
+Hope all is well with you too.
+
+Cheers,
+Erik
+- Hide quoted text -
+
+On Tue, Apr 29, 2008 at 3:13 PM, martin odersky <martin.odersky@epfl.ch> wrote:
+
+    Hi Erik,
+
+    I tried to send mail to happi@home.se, but got a response n swedish. I
+    was sort of guessing from the response that it contained an
+    alternative e-mail address and tried to send it there.
+
+    Anyway,  I hope things are going well with you!
+
+    There was some discussion recently about the license of Tree.scala in
+    package collection.immutable. It's GPL, whereas the rest of the Scala
+    library is BSD. It seems this poses problems with Scala being packaged
+    with Fedora. Would it be OK with you to change the license to the
+    general one of Scala libraries? You could simply remove the references
+    to the GPL
+    license in the code and send it back to me if that's OK with you. On
+    the other hand, if there's a problem we'll try something else instead.
+
+    All the best
+
+     -- Martin
+*/