Merge 2.10.x to master (plus a test) #92
Merged
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
`TreeGen#mkZero` returns `q"null"` for derived value classes.
```
scala> class V(val a: String) extends AnyVal
defined class V
scala> showRaw(gen.mkZero(typeOf[V]))
res0: String = Literal(Constant(null))
```
We use this API in async to generate the initial value for
ANF-lifted temporary variables.
However, this leads to NPEs, as after posterasure, we call the
unbox method on a null reference:
```
% cat sandbox/Macro.scala; scalac-hash v2.10.4 sandbox/Macro.scala; scala-hash v2.10.4 -e 'val x = Macros.myMacro'
import scala.reflect.macros.Context
import scala.language.experimental.macros
object Macros {
def macroImpl(c: Context): c.Expr[C] = {
import c.universe._
val e1 = c.Expr[C](Literal(Constant(null)).setType(typeOf[C]))
reify(e1.splice.asInstanceOf[C @annotation.unchecked.uncheckedVariance])
}
def myMacro: C = macro macroImpl
}
class C(val a: String) extends AnyVal
java.lang.NullPointerException
at Main$$anon$1.<init>(scalacmd4059893593754060829.scala:1)
at Main$.main(scalacmd4059893593754060829.scala:1)
at Main.main(scalacmd4059893593754060829.scala)
```
This commit installs a custom version of `mkZero` that instead
returns `q"new C[$..targs](${mkZero(wrappedType)})`.
Thanks to @ewiner for pinpointing the problem.
Conflicts: src/main/scala/scala/async/internal/AnfTransform.scala src/main/scala/scala/async/internal/AsyncTransform.scala src/test/scala/scala/async/run/toughtype/ToughType.scala
|
I'm going to merge this one now as I'm ready to cut the next release. Post hoc review still welcome. |
retronym
added a commit
that referenced
this pull request
Oct 2, 2014
Merge 2.10.x to master (plus a test)
|
LGTM |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Review by @phaller