diff options
| -rw-r--r-- | src/compiler/scala/tools/nsc/transform/TailCalls.scala | 21 | ||||
| -rw-r--r-- | test/files/neg/t3275.check | 4 | ||||
| -rw-r--r-- | test/files/neg/t3275.scala | 3 | ||||
| -rw-r--r-- | test/files/neg/t5455.check | 4 | ||||
| -rw-r--r-- | test/files/neg/t5455.scala | 16 | ||||
| -rw-r--r-- | test/files/neg/tailrec-2.check | 7 | ||||
| -rw-r--r-- | test/files/neg/tailrec-2.scala | 3 |
7 files changed, 54 insertions, 4 deletions
diff --git a/src/compiler/scala/tools/nsc/transform/TailCalls.scala b/src/compiler/scala/tools/nsc/transform/TailCalls.scala index 848d6be47b..fdb5c7e52e 100644 --- a/src/compiler/scala/tools/nsc/transform/TailCalls.scala +++ b/src/compiler/scala/tools/nsc/transform/TailCalls.scala @@ -223,8 +223,25 @@ abstract class TailCalls extends Transform { } tree match { - case dd @ DefDef(_, _, _, vparamss0, _, rhs0) => + case ValDef(_, _, _, _) => + if (tree.symbol.isLazy && tree.symbol.hasAnnotation(TailrecClass)) + unit.error(tree.pos, "lazy vals are not tailcall transformed") + + super.transform(tree) + + case dd @ DefDef(_, _, _, vparamss0, _, rhs0) if !dd.symbol.hasAccessorFlag => val newCtx = new Context(dd) + def isRecursiveCall(t: Tree) = { + val sym = t.symbol + (sym != null) && { + sym.isMethod && (dd.symbol.name == sym.name) && (dd.symbol.enclClass isSubClass sym.enclClass) + } + } + if (newCtx.isMandatory) { + if (!rhs0.exists(isRecursiveCall)) { + unit.error(tree.pos, "@tailrec annotated method contains no recursive calls") + } + } debuglog("Considering " + dd.name + " for tailcalls") val newRHS = transform(rhs0, newCtx) @@ -248,7 +265,7 @@ abstract class TailCalls extends Transform { )) } else { - if (newCtx.isMandatory) + if (newCtx.isMandatory && newRHS.exists(isRecursiveCall)) newCtx.tailrecFailure() newRHS diff --git a/test/files/neg/t3275.check b/test/files/neg/t3275.check new file mode 100644 index 0000000000..117c792321 --- /dev/null +++ b/test/files/neg/t3275.check @@ -0,0 +1,4 @@ +t3275.scala:2: error: @tailrec annotated method contains no recursive calls + @annotation.tailrec def foo() = 5 + ^ +one error found diff --git a/test/files/neg/t3275.scala b/test/files/neg/t3275.scala new file mode 100644 index 0000000000..18e38a1a97 --- /dev/null +++ b/test/files/neg/t3275.scala @@ -0,0 +1,3 @@ +object Test { + @annotation.tailrec def foo() = 5 +} diff --git a/test/files/neg/t5455.check b/test/files/neg/t5455.check new file mode 100644 index 0000000000..788daf99fa --- /dev/null +++ b/test/files/neg/t5455.check @@ -0,0 +1,4 @@ +t5455.scala:4: error: lazy vals are not tailcall transformed + @annotation.tailrec final lazy val bar: Thing[Int] = { + ^ +one error found diff --git a/test/files/neg/t5455.scala b/test/files/neg/t5455.scala new file mode 100644 index 0000000000..22d6c442c9 --- /dev/null +++ b/test/files/neg/t5455.scala @@ -0,0 +1,16 @@ +trait Test { + def root: Test + + @annotation.tailrec final lazy val bar: Thing[Int] = { + if (this eq root) + Thing(() => System.identityHashCode(bar)) + else + root.bar + } + + def f = bar.f() +} + +case class Thing[A](f: () => A) { + override def toString = "" + f() +} diff --git a/test/files/neg/tailrec-2.check b/test/files/neg/tailrec-2.check index 4f763a1c8d..a918858773 100644 --- a/test/files/neg/tailrec-2.check +++ b/test/files/neg/tailrec-2.check @@ -1,4 +1,7 @@ -tailrec-2.scala:6: error: could not optimize @tailrec annotated method f: it contains a recursive call targetting a supertype +tailrec-2.scala:8: error: could not optimize @tailrec annotated method f: it contains a recursive call targetting a supertype @annotation.tailrec final def f[B >: A](mem: List[B]): List[B] = (null: Super[A]).f(mem) ^ -one error found +tailrec-2.scala:9: error: @tailrec annotated method contains no recursive calls + @annotation.tailrec final def f1[B >: A](mem: List[B]): List[B] = this.g(mem) + ^ +two errors found diff --git a/test/files/neg/tailrec-2.scala b/test/files/neg/tailrec-2.scala index 342cd85323..9eb3af2f07 100644 --- a/test/files/neg/tailrec-2.scala +++ b/test/files/neg/tailrec-2.scala @@ -1,9 +1,12 @@ sealed abstract class Super[+A] { def f[B >: A](mem: List[B]) : List[B] + def g(mem: List[_]) = ??? } // This one should fail, target is a supertype class Bop1[+A](val element: A) extends Super[A] { + @annotation.tailrec final def f[B >: A](mem: List[B]): List[B] = (null: Super[A]).f(mem) + @annotation.tailrec final def f1[B >: A](mem: List[B]): List[B] = this.g(mem) } // These succeed class Bop2[+A](val element: A) extends Super[A] { |