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author | Jason Zaugg <jzaugg@gmail.com> | 2012-05-11 00:11:45 +0200 |
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committer | Jason Zaugg <jzaugg@gmail.com> | 2012-05-11 07:31:20 +0200 |
commit | d35e74eb6bc13f1f354029c9439cef35aecd972b (patch) | |
tree | 14f4e936bd3bf381f97370aa5233b7c9f871fdf4 | |
parent | df10f921158ea13ce8fb53c8e15ec290ace69d83 (diff) | |
download | scala-d35e74eb6bc13f1f354029c9439cef35aecd972b.tar.gz scala-d35e74eb6bc13f1f354029c9439cef35aecd972b.tar.bz2 scala-d35e74eb6bc13f1f354029c9439cef35aecd972b.zip |
Forbid forward refs from self constructor invocations.
Prevents the wheels falling off during later compiler phases,
or, worse, during bytecode verification.
Closes SI-4098.
-rw-r--r-- | src/compiler/scala/tools/nsc/typechecker/RefChecks.scala | 9 | ||||
-rw-r--r-- | test/files/neg/t4098.check | 13 | ||||
-rw-r--r-- | test/files/neg/t4098.scala | 22 |
3 files changed, 44 insertions, 0 deletions
diff --git a/src/compiler/scala/tools/nsc/typechecker/RefChecks.scala b/src/compiler/scala/tools/nsc/typechecker/RefChecks.scala index 6bed0b1228..b04d768baa 100644 --- a/src/compiler/scala/tools/nsc/typechecker/RefChecks.scala +++ b/src/compiler/scala/tools/nsc/typechecker/RefChecks.scala @@ -1279,6 +1279,15 @@ abstract class RefChecks extends InfoTransform with reflect.internal.transform.R } def transformStat(tree: Tree, index: Int): List[Tree] = tree match { + case Apply(Select(This(_), nme.CONSTRUCTOR), args) => + assert(index == 0, index) + val t = transform(tree) + if (currentLevel.maxindex > 0) { + // An implementation restriction to avoid VerifyErrors and lazyvals mishaps; see SI-4717 + debuglog("refsym = " + currentLevel.refsym) + unit.error(currentLevel.refpos, "forward reference not allowed from self constructor invocation") + } + List(t) case ModuleDef(_, _, _) => eliminateModuleDefs(tree) case ValDef(_, _, _, _) => val tree1 @ ValDef(_, _, _, rhs) = transform(tree) // important to do before forward reference check diff --git a/test/files/neg/t4098.check b/test/files/neg/t4098.check new file mode 100644 index 0000000000..7d69cf151c --- /dev/null +++ b/test/files/neg/t4098.check @@ -0,0 +1,13 @@ +t4098.scala:3: error: forward reference not allowed from self constructor invocation + this(b) + ^ +t4098.scala:8: error: forward reference not allowed from self constructor invocation + this(b) + ^ +t4098.scala:13: error: forward reference not allowed from self constructor invocation + this(b) + ^ +t4098.scala:18: error: forward reference not allowed from self constructor invocation + this(b) + ^ +four errors found diff --git a/test/files/neg/t4098.scala b/test/files/neg/t4098.scala new file mode 100644 index 0000000000..744d6191b5 --- /dev/null +++ b/test/files/neg/t4098.scala @@ -0,0 +1,22 @@ +class A(a: Any) { + def this() = { + this(b) + def b = new {} + } + + def this(x: Int) = { + this(b) + lazy val b = new {} + } + + def this(x: Int, y: Int) = { + this(b) + val b = new {} + } + + def this(x: Int, y: Int, z: Int) = { + this(b) + println(".") + def b = new {} + } +} |