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20 hours ago •
scala
scala
extends + type refinement = slaying of typer
compiler crashers are a dime a dozen, but finding a nice short one is worth a whole dime all by itself:
trait T extends (Any{})
up to 2.9 we were okay:
Welcome to Scala version 2.9.3 (Java HotSpot(TM) 64-Bit Server VM, Java 1.6.0_65).
scala> trait T extends (Any{})
<console>:7: error: class type required but Any found
trait T extends (Any{})
but starting with 2.10 it crashes. here's the 2.12.3 transcript:
scala> trait T extends (Any{})
java.lang.AssertionError: assertion failed: transformCaseApply: name = Any! tree = Any / class scala.reflect.internal.Trees$Ident
at scala.tools.nsc.typechecker.RefChecks$RefCheckTransformer.transform(RefChecks.scala:1703)
at scala.tools.nsc.typechecker.RefChecks$RefCheckTransformer.transform(RefChecks.scala:107)
at scala.reflect.api.Trees$Transformer.$anonfun$transformTrees$1(Trees.scala:2559)
at scala.reflect.api.Trees$Transformer.transformTrees(Trees.scala:2559)
at scala.reflect.internal.Trees.itransform(Trees.scala:1415)
at scala.reflect.internal.Trees.itransform$(Trees.scala:1347)
at scala.reflect.internal.SymbolTable.itransform(SymbolTable.scala:16)
at scala.reflect.internal.SymbolTable.itransform(SymbolTable.scala:16)
at scala.reflect.api.Trees$Transformer.transform(Trees.scala:2555)
at scala.tools.nsc.typechecker.RefChecks$RefCheckTransformer.transform(RefChecks.scala:1750)
at scala.tools.nsc.typechecker.RefChecks$RefCheckTransformer.transform(RefChecks.scala:107)
at scala.reflect.api.Trees$Transformer.transformTemplate(Trees.scala:2563)
at scala.reflect.internal.Trees.itransform(Trees.scala:1447)
at scala.reflect.internal.Trees.itransform$(Trees.scala:1347)
at scala.reflect.internal.SymbolTable.itransform(SymbolTable.scala:16)
at scala.reflect.internal.SymbolTable.itransform(SymbolTable.scala:16)
at scala.reflect.api.Trees$Transformer.transform(Trees.scala:2555)
at scala.tools.nsc.typechecker.RefChecks$RefCheckTransformer.transform(RefChecks.scala:1750)
at scala.tools.nsc.typechecker.RefChecks$RefCheckTransformer.transform(RefChecks.scala:107)
at scala.reflect.api.Trees$Transformer.$anonfun$transformTrees$1(Trees.scala:2559)
at scala.reflect.api.Trees$Transformer.transformTrees(Trees.scala:2559)
at scala.reflect.internal.Trees.itransform(Trees.scala:1415)
at scala.reflect.internal.Trees.itransform$(Trees.scala:1347)
at scala.reflect.internal.SymbolTable.itransform(SymbolTable.scala:16)
at scala.reflect.internal.SymbolTable.itransform(SymbolTable.scala:16)
at scala.reflect.api.Trees$Transformer.transform(Trees.scala:2555)
at scala.tools.nsc.typechecker.RefChecks$RefCheckTransformer.transform(RefChecks.scala:1750)
at scala.tools.nsc.typechecker.RefChecks$RefCheckTransformer.transform(RefChecks.scala:107)
at scala.reflect.api.Trees$Transformer.transformTemplate(Trees.scala:2563)
at scala.reflect.internal.Trees.$anonfun$itransform$4(Trees.scala:1419)
at scala.reflect.api.Trees$Transformer.atOwner(Trees.scala:2600)
at scala.reflect.internal.Trees.itransform(Trees.scala:1418)
at scala.reflect.internal.Trees.itransform$(Trees.scala:1347)
at scala.reflect.internal.SymbolTable.itransform(SymbolTable.scala:16)
at scala.reflect.internal.SymbolTable.itransform(SymbolTable.scala:16)
at scala.reflect.api.Trees$Transformer.transform(Trees.scala:2555)
at scala.tools.nsc.typechecker.RefChecks$RefCheckTransformer.transform(RefChecks.scala:1750)
at scala.tools.nsc.typechecker.RefChecks$RefCheckTransformer.transformStat(RefChecks.scala:1197)
at scala.tools.nsc.typechecker.RefChecks$RefCheckTransformer.$anonfun$transformStats$1(RefChecks.scala:1168)
at scala.tools.nsc.typechecker.RefChecks$RefCheckTransformer.transformStats(RefChecks.scala:1168)
at scala.tools.nsc.typechecker.RefChecks$RefCheckTransformer.transformStats(RefChecks.scala:107)
at scala.reflect.internal.Trees.itransform(Trees.scala:1415)
at scala.reflect.internal.Trees.itransform$(Trees.scala:1347)
at scala.reflect.internal.SymbolTable.itransform(SymbolTable.scala:16)
at scala.reflect.internal.SymbolTable.itransform(SymbolTable.scala:16)
at scala.reflect.api.Trees$Transformer.transform(Trees.scala:2555)
at scala.tools.nsc.typechecker.RefChecks$RefCheckTransformer.transform(RefChecks.scala:1750)
at scala.tools.nsc.typechecker.RefChecks$RefCheckTransformer.transform(RefChecks.scala:107)
at scala.reflect.api.Trees$Transformer.transformTemplate(Trees.scala:2563)
at scala.reflect.internal.Trees.$anonfun$itransform$5(Trees.scala:1424)
at scala.reflect.api.Trees$Transformer.atOwner(Trees.scala:2600)
at scala.reflect.internal.Trees.itransform(Trees.scala:1423)
at scala.reflect.internal.Trees.itransform$(Trees.scala:1347)
at scala.reflect.internal.SymbolTable.itransform(SymbolTable.scala:16)
at scala.reflect.internal.SymbolTable.itransform(SymbolTable.scala:16)
at scala.reflect.api.Trees$Transformer.transform(Trees.scala:2555)
at scala.tools.nsc.typechecker.RefChecks$RefCheckTransformer.transform(RefChecks.scala:1750)
at scala.tools.nsc.typechecker.RefChecks$RefCheckTransformer.transformStat(RefChecks.scala:1197)
at scala.tools.nsc.typechecker.RefChecks$RefCheckTransformer.$anonfun$transformStats$1(RefChecks.scala:1168)
at scala.tools.nsc.typechecker.RefChecks$RefCheckTransformer.transformStats(RefChecks.scala:1168)
at scala.tools.nsc.typechecker.RefChecks$RefCheckTransformer.transformStats(RefChecks.scala:107)
at scala.reflect.internal.Trees.itransform(Trees.scala:1415)
at scala.reflect.internal.Trees.itransform$(Trees.scala:1347)
at scala.reflect.internal.SymbolTable.itransform(SymbolTable.scala:16)
at scala.reflect.internal.SymbolTable.itransform(SymbolTable.scala:16)
at scala.reflect.api.Trees$Transformer.transform(Trees.scala:2555)
at scala.tools.nsc.typechecker.RefChecks$RefCheckTransformer.transform(RefChecks.scala:1750)
at scala.tools.nsc.typechecker.RefChecks$RefCheckTransformer.transform(RefChecks.scala:107)
at scala.reflect.api.Trees$Transformer.transformTemplate(Trees.scala:2563)
at scala.reflect.internal.Trees.$anonfun$itransform$5(Trees.scala:1424)
at scala.reflect.api.Trees$Transformer.atOwner(Trees.scala:2600)
at scala.reflect.internal.Trees.itransform(Trees.scala:1423)
at scala.reflect.internal.Trees.itransform$(Trees.scala:1347)
at scala.reflect.internal.SymbolTable.itransform(SymbolTable.scala:16)
at scala.reflect.internal.SymbolTable.itransform(SymbolTable.scala:16)
at scala.reflect.api.Trees$Transformer.transform(Trees.scala:2555)
at scala.tools.nsc.typechecker.RefChecks$RefCheckTransformer.transform(RefChecks.scala:1750)
at scala.tools.nsc.typechecker.RefChecks$RefCheckTransformer.transformStat(RefChecks.scala:1197)
at scala.tools.nsc.typechecker.RefChecks$RefCheckTransformer.$anonfun$transformStats$1(RefChecks.scala:1168)
at scala.tools.nsc.typechecker.RefChecks$RefCheckTransformer.transformStats(RefChecks.scala:1168)
at scala.tools.nsc.typechecker.RefChecks$RefCheckTransformer.transformStats(RefChecks.scala:107)
at scala.reflect.internal.Trees.itransform(Trees.scala:1415)
at scala.reflect.internal.Trees.itransform$(Trees.scala:1347)
at scala.reflect.internal.SymbolTable.itransform(SymbolTable.scala:16)
at scala.reflect.internal.SymbolTable.itransform(SymbolTable.scala:16)
at scala.reflect.api.Trees$Transformer.transform(Trees.scala:2555)
at scala.tools.nsc.typechecker.RefChecks$RefCheckTransformer.transform(RefChecks.scala:1750)
at scala.tools.nsc.typechecker.RefChecks$RefCheckTransformer.transform(RefChecks.scala:107)
at scala.reflect.api.Trees$Transformer.transformTemplate(Trees.scala:2563)
at scala.reflect.internal.Trees.$anonfun$itransform$5(Trees.scala:1424)
at scala.reflect.api.Trees$Transformer.atOwner(Trees.scala:2600)
at scala.reflect.internal.Trees.itransform(Trees.scala:1423)
at scala.reflect.internal.Trees.itransform$(Trees.scala:1347)
at scala.reflect.internal.SymbolTable.itransform(SymbolTable.scala:16)
at scala.reflect.internal.SymbolTable.itransform(SymbolTable.scala:16)
at scala.reflect.api.Trees$Transformer.transform(Trees.scala:2555)
at scala.tools.nsc.typechecker.RefChecks$RefCheckTransformer.transform(RefChecks.scala:1750)
at scala.tools.nsc.typechecker.RefChecks$RefCheckTransformer.transformStat(RefChecks.scala:1197)
at scala.tools.nsc.typechecker.RefChecks$RefCheckTransformer.$anonfun$transformStats$1(RefChecks.scala:1168)
at scala.tools.nsc.typechecker.RefChecks$RefCheckTransformer.transformStats(RefChecks.scala:1168)
at scala.tools.nsc.typechecker.RefChecks$RefCheckTransformer.transformStats(RefChecks.scala:107)
at scala.reflect.internal.Trees.$anonfun$itransform$7(Trees.scala:1437)
at scala.reflect.api.Trees$Transformer.atOwner(Trees.scala:2600)
at scala.reflect.internal.Trees.itransform(Trees.scala:1437)
at scala.reflect.internal.Trees.itransform$(Trees.scala:1347)
at scala.reflect.internal.SymbolTable.itransform(SymbolTable.scala:16)
at scala.reflect.internal.SymbolTable.itransform(SymbolTable.scala:16)
at scala.reflect.api.Trees$Transformer.transform(Trees.scala:2555)
at scala.tools.nsc.typechecker.RefChecks$RefCheckTransformer.transform(RefChecks.scala:1750)
at scala.tools.nsc.typechecker.RefChecks$RefCheckTransformer.transform(RefChecks.scala:107)
at scala.tools.nsc.ast.Trees$Transformer.transformUnit(Trees.scala:140)
at scala.tools.nsc.transform.Transform$Phase.apply(Transform.scala:30)
at scala.tools.nsc.Global$GlobalPhase.$anonfun$applyPhase$1(Global.scala:426)
at scala.tools.nsc.Global$GlobalPhase.applyPhase(Global.scala:419)
at scala.tools.nsc.Global$GlobalPhase.$anonfun$run$1(Global.scala:390)
at scala.tools.nsc.Global$GlobalPhase.$anonfun$run$1$adapted(Global.scala:390)
at scala.collection.Iterator.foreach(Iterator.scala:929)
at scala.collection.Iterator.foreach$(Iterator.scala:929)
at scala.collection.AbstractIterator.foreach(Iterator.scala:1417)
at scala.tools.nsc.Global$GlobalPhase.run(Global.scala:390)
at scala.tools.nsc.Global$Run.compileUnitsInternal(Global.scala:1431)
at scala.tools.nsc.Global$Run.compileUnits(Global.scala:1416)
at scala.tools.nsc.Global$Run.compileSources(Global.scala:1412)
at scala.tools.nsc.interpreter.IMain.compileSourcesKeepingRun(IMain.scala:431)
at scala.tools.nsc.interpreter.IMain$ReadEvalPrint.compileAndSaveRun(IMain.scala:800)
at scala.tools.nsc.interpreter.IMain$ReadEvalPrint.compile(IMain.scala:758)
at scala.tools.nsc.interpreter.IMain$Request.compile$lzycompute(IMain.scala:947)
at scala.tools.nsc.interpreter.IMain$Request.compile(IMain.scala:942)
at scala.tools.nsc.interpreter.IMain.compile(IMain.scala:600)
at scala.tools.nsc.interpreter.IMain.interpret(IMain.scala:589)
at scala.tools.nsc.interpreter.IMain.interpret(IMain.scala:561)
at scala.tools.nsc.interpreter.ILoop.interpretStartingWith(ILoop.scala:870)
at scala.tools.nsc.interpreter.ILoop.command(ILoop.scala:738)
at scala.tools.nsc.interpreter.ILoop.processLine(ILoop.scala:456)
at scala.tools.nsc.interpreter.ILoop.loop(ILoop.scala:477)
at scala.tools.nsc.interpreter.ILoop.$anonfun$process$1(ILoop.scala:1070)
at scala.tools.nsc.interpreter.ILoop.process(ILoop.scala:949)
at scala.tools.nsc.MainGenericRunner.runTarget$1(MainGenericRunner.scala:82)
at scala.tools.nsc.MainGenericRunner.run$1(MainGenericRunner.scala:85)
at scala.tools.nsc.MainGenericRunner.process(MainGenericRunner.scala:96)
at scala.tools.nsc.MainGenericRunner$.main(MainGenericRunner.scala:101)
at scala.tools.nsc.MainGenericRunner.main(MainGenericRunner.scala)
That entry seems to have slain the compiler. Shall I replay
your session? I can re-run each line except the last one.
[y/n]
