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The Scala 3 compiler, also known as Dotty.
https://dotty.epfl.ch
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Dotty cannot read Scalac @specialized annotations #205

Closed DarkDimius closed 9 years ago

DarkDimius commented 9 years ago

https://github.com/lampepfl/dotty/blob/master/src/dotty/tools/dotc/core/pickling/UnPickler.scala#L829 Dotty always assumes that default constructor of annotation is called. That's not true for common case of @specialized(Int).

odersky commented 9 years ago

Ouch. It looks like the Unpickler has to invoke resolveOverloaded to get to the right constructor. That's not nice at all, but I do not see a better alternative.

DarkDimius commented 9 years ago

I was able to reuse resolveOverloaded to get overloading resolution and ApplyToTyped to get argument adaptation(eg varagrs handling). But now I see failures due to resolveOverloaded executing narrowByTrees(alts2, pt.typedArgs, resultType) ie: trying to retype argument trees. Which fails due to those trees not having a position set.

This rises a question of should positions be set for annotation trees read from bytecode or not. As those trees aren't representing a code that is in control of user I would say that any synthetic position should be ok.

@odersky, Do you have a better idea?

odersky commented 9 years ago

Good that resolveOverloaded works. I don't see right now how narrowByTrees would fail because of missing positions. Let's see a stacktrace tomorrow.

On Wed, Oct 29, 2014 at 9:47 PM, Dmitry Petrashko notifications@github.com wrote:

I was able to reuse resolveOverloaded to get overloading resolution and ApplyToTyped to get argument adaptation(eg varagrs handling). But now I see failures due to resolveOverloaded executing narrowByTrees(alts2, pt.typedArgs, resultType) https://github.com/lampepfl/dotty/blob/master/src/dotty/tools/dotc/typer/Applications.scala#L953 ie: trying to retype argument trees. Which fails due to those trees not having a position set.

This rises a question of should positions be set for annotation trees read from bytecode or not. As those trees aren't representing a code that is in control of user I would say that any synthetic position should be ok.

@odersky https://github.com/odersky, Do you have a better idea?

— Reply to this email directly or view it on GitHub https://github.com/lampepfl/dotty/issues/205#issuecomment-61001910.

Martin Odersky EPFL

DarkDimius commented 9 years ago

should be fixed in #206