diff options
-rw-r--r-- | src/compiler/scala/tools/nsc/transform/Erasure.scala | 13 | ||||
-rw-r--r-- | test/files/run/t8010.scala | 22 |
2 files changed, 35 insertions, 0 deletions
diff --git a/src/compiler/scala/tools/nsc/transform/Erasure.scala b/src/compiler/scala/tools/nsc/transform/Erasure.scala index 6fe0f34105..6732900ef2 100644 --- a/src/compiler/scala/tools/nsc/transform/Erasure.scala +++ b/src/compiler/scala/tools/nsc/transform/Erasure.scala @@ -714,11 +714,24 @@ abstract class Erasure extends AddInterfaces /** TODO - adapt SymbolPairs so it can be used here. */ private def checkNoDeclaredDoubleDefs(base: Symbol) { val decls = base.info.decls + + // SI-8010 force infos, otherwise makeNotPrivate in ExplicitOuter info transformer can trigger + // a scope rehash while were iterating and we can see the same entry twice! + // Inspection of SymbolPairs (the basis of OverridingPairs), suggests that it is immune + // from this sort of bug as it copies the symbols into a temporary scope *before* any calls to `.info`, + // ie, no variant of it calls `info` or `tpe` in `SymbolPair#exclude`. + // + // Why not just create a temporary scope here? We need to force the name changes in any case before + // we do these checks, so that we're comparing same-named methods based on the expanded names that actually + // end up in the bytecode. + exitingPostErasure(decls.foreach(_.info)) + var e = decls.elems while (e ne null) { if (e.sym.isTerm) { var e1 = decls lookupNextEntry e while (e1 ne null) { + assert(e.sym ne e1.sym, s"Internal error: encountered ${e.sym.debugLocationString} twice during scope traversal. This might be related to SI-8010.") if (sameTypeAfterErasure(e.sym, e1.sym)) doubleDefError(new SymbolPair(base, e.sym, e1.sym)) diff --git a/test/files/run/t8010.scala b/test/files/run/t8010.scala new file mode 100644 index 0000000000..8636bbd12e --- /dev/null +++ b/test/files/run/t8010.scala @@ -0,0 +1,22 @@ +trait Base { + def t = 1 + def t(n: Int) = n + def bt = 2 + def bt(n: Int) = n +} +trait Derived extends Base { + // was: double defintion error + override def t = 1 + super.t + override def t(n: Int) = 1 + super.t(n) + override def bt = 1 + super.bt + override def bt(n: Int) = 1 + super.bt(n) +} + +object Test extends App { + val d = new Derived {} + // not the focus of thie bug, but let's just check the runtime behaviour while we're here. + assert(d.t == 2) + assert(d.t(1) == 2) + assert(d.bt == 3) + assert(d.bt(1) == 2) +} |