Debugging specialization stack traces

On Sat, May 1, 2010 at 9:38 AM, David Hall <dlwh@cs.berkeley.edu> wrote:

-Ylog:specialization has been my usual trick of choice for finding
these bugs, but in this case it looks like specialized has gone far
beyond my user code before it stumbles into this error. There are
roughly 100 lines of specialized-related output between the last
mention of one of my classes, and where the exception is thrown. Are
there any other tricks or magical compiler flags to help find what's
wrong?

Part of specialization happens at the next phase, explicitouter. That's in fact where all type errors may happen, so you could try -Ylog:expl. -Ydebug adds even more logging. 
If you cannot reduce the crash to a small example, that's ok, post a ticket anyway, with a link to the project, or an archive of your source code.
iulian 

Thanks,
David

java.lang.Error: no-symbol does not have owner
       at scala.tools.nsc.symtab.SymbolTable.abort(SymbolTable.scala:34)
       at scala.tools.nsc.symtab.Symbols$NoSymbol$.owner(Symbols.scala:2036)
       at scala.tools.nsc.ast.TreeGen.isInPkgObject$1(TreeGen.scala:164)
       at scala.tools.nsc.ast.TreeGen.mkAttributedSelect(TreeGen.scala:170)
       at scala.tools.nsc.ast.TreeGen.mkAttributedRef(TreeGen.scala:113)
       at scala.tools.nsc.transform.SpecializeTypes$$anon$6.transform(SpecializeTypes.scala:1117)
       at scala.tools.nsc.ast.Trees$Transformer$$anonfun$transformTrees$1.apply(Trees.scala:831)
       at scala.tools.nsc.ast.Trees$Transformer$$anonfun$transformTrees$1.apply(Trees.scala:831)
       at scala.collection.immutable.List.loop$1(List.scala:116)
       at scala.collection.immutable.List.mapConserve(List.scala:133)
       at scala.collection.immutable.List.loop$1(List.scala:120)
       at scala.collection.immutable.List.mapConserve(List.scala:133)
       at scala.collection.immutable.List.loop$1(List.scala:120)
       at scala.collection.immutable.List.mapConserve(List.scala:133)
       at scala.collection.immutable.List.loop$1(List.scala:120)
       at scala.collection.immutable.List.mapConserve(List.scala:133)
       at scala.collection.immutable.List.loop$1(List.scala:120)
       at scala.collection.immutable.List.mapConserve(List.scala:133)
       at scala.collection.immutable.List.loop$1(List.scala:120)
       at scala.collection.immutable.List.mapConserve(List.scala:133)
       at scala.collection.immutable.List.loop$1(List.scala:120)
       at scala.collection.immutable.List.mapConserve(List.scala:133)
       at scala.collection.immutable.List.loop$1(List.scala:120)
       at scala.collection.immutable.List.mapConserve(List.scala:133)
       at scala.tools.nsc.ast.Trees$Transformer.transformTrees(Trees.scala:831)
       at scala.tools.nsc.transform.SpecializeTypes$$anon$6$$anonfun$transform$3.apply(SpecializeTypes.scala:1038)
       at scala.tools.nsc.transform.SpecializeTypes$$anon$6$$anonfun$transform$3.apply(SpecializeTypes.scala:1038)
       at scala.tools.nsc.ast.Trees$Transformer.atOwner(Trees.scala:857)
       at scala.tools.nsc.transform.TypingTransformers$TypingTransformer.atOwner(TypingTransformers.scala:36)
       at scala.tools.nsc.transform.TypingTransformers$TypingTransformer.atOwner(TypingTransformers.scala:29)
       at scala.tools.nsc.transform.SpecializeTypes$$anon$6.transform(SpecializeTypes.scala:1038)
 (pruned here, if you want the whole thing, let me know)

--
« Je déteste la montagne, ça cache le paysage »
Alphonse Allais

On Sun, May 2, 2010 at 1:11 AM, Iulian Dragos wrote:
> Part of specialization happens at the next phase, explicitouter. That's in
> fact where all type errors may happen, so you could try -Ylog:expl. -Ydebug
> adds even more logging.

Ok, thanks!

> If you cannot reduce the crash to a small example, that's ok, post a ticket
> anyway, with a link to the project, or an archive of your source code.

ok, I'm unfortunately swamped for the next two weeks, and so I think I
have to give up and give you a code pointer. The Ticket is #3387,
which includes the link, and some compiler output.

Thanks!