SI-6384 - avoid crash due to optimization in 2.10 CPS plugin

This fixes a regression in the 2.9.x branch (code combining CPS and
try-catch crashing the compiler).  The fix is simply undoing an
optimization that was done in the 2.10 CPS plugin (replacing a
function with only a match by a match on an empty tree).

3 files changed, 37 insertions, 1 deletions

diff --git a/src/continuations/plugin/scala/tools/selectivecps/SelectiveCPSTransform.scala b/src/continuations/plugin/scala/tools/selectivecps/SelectiveCPSTransform.scala
index a9900429ed..3cf0ce80ea 100644
--- a/src/continuations/plugin/scala/tools/selectivecps/SelectiveCPSTransform.scala
+++ b/src/continuations/plugin/scala/tools/selectivecps/SelectiveCPSTransform.scala
@@ -191,14 +191,19 @@ abstract class SelectiveCPSTransform extends PluginComponent with
 
           val pos = catches.head.pos
           val funSym = currentOwner.newValueParameter(pos, cpsNames.catches).setInfo(appliedType(PartialFunctionClass.tpe, List(ThrowableClass.tpe, targettp)))
+          val argSym = currentOwner.newValueParameter(pos, cpsNames.ex).setInfo(ThrowableClass.tpe)
+          val rhs = Match(Ident(argSym), catches1)
+          val fun = Function(List(ValDef(argSym)), rhs)
           val funDef = localTyper.typed(atPos(pos) {
-            ValDef(funSym, Match(EmptyTree, catches1))
+            ValDef(funSym, fun)
           })
           val expr2 = localTyper.typed(atPos(pos) {
             Apply(Select(expr1, expr1.tpe.member(cpsNames.flatMapCatch)), List(Ident(funSym)))
           })
 
           val exSym = currentOwner.newValueParameter(pos, cpsNames.ex).setInfo(ThrowableClass.tpe)
+          exSym.owner = fun.symbol
+          rhs.changeOwner(currentOwner -> fun.symbol)
 
           import CODE._
           // generate a case that is supported directly by the back-end
diff --git a/test/files/continuations-run/trycatch3.check b/test/files/continuations-run/trycatch3.check
new file mode 100644
index 0000000000..7ed6ff82de
--- /dev/null
+++ b/test/files/continuations-run/trycatch3.check
@@ -0,0 +1 @@
+5
diff --git a/test/files/continuations-run/trycatch3.scala b/test/files/continuations-run/trycatch3.scala
new file mode 100644
index 0000000000..c4bfb702de
--- /dev/null
+++ b/test/files/continuations-run/trycatch3.scala
@@ -0,0 +1,30 @@
+import scala.util.continuations._
+
+trait Result
+case class ValueResult(value: Int) extends Result
+case class ErrorResult(err: Exception) extends Result
+
+class Foo {
+  def func: Int @cpsParam[Any, Any] = shiftUnit[Int, Any, Any](5)
+}
+
+object Test extends App {
+  val foo = new Foo
+
+  def f: Result @cpsParam[Any, Any] = {
+    try {
+      //ValueResult(foo.func)
+      throw new Exception("" + foo.func)
+    }
+    catch {
+      case ex: Exception => ErrorResult(ex)
+    }
+  }
+
+  reset {
+    f match {
+      case ValueResult(x)  => println(x)
+      case ErrorResult(ex) => println(ex.getMessage())
+    }
+  }
+}