From c82bc67737a31f2a639172e677cafdefe8fdbf4e Mon Sep 17 00:00:00 2001 From: Jason Zaugg Date: Sat, 26 May 2012 22:49:12 +0200 Subject: Fix a NSDNHAO in extension methods. A bridge method, created when we override a method from a superclass and refine the return type, was appearing as an overloaded alternative. (`erasure` doesn't create new scopes, so the bridges it builds are visible at earlier phases.) The problem was masked when compiling with specialization, which *does* create a new scope, shielding the code in question from the artefacts of erasure. To fix the problem, we filter out bridge methods from the overloaded alternatives returned by `.decl`, as would happen internally in `.member`. --- .../scala/tools/nsc/transform/ExtensionMethods.scala | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-) (limited to 'src/compiler') diff --git a/src/compiler/scala/tools/nsc/transform/ExtensionMethods.scala b/src/compiler/scala/tools/nsc/transform/ExtensionMethods.scala index 007457ef7b..8556cc9ddc 100644 --- a/src/compiler/scala/tools/nsc/transform/ExtensionMethods.scala +++ b/src/compiler/scala/tools/nsc/transform/ExtensionMethods.scala @@ -44,8 +44,18 @@ abstract class ExtensionMethods extends Transform with TypingTransformers { * in `extensionMethod` if the first name has the wrong type. We thereby gain a level of insensitivity * of how overloaded types are ordered between phases and picklings. */ - private def extensionNames(imeth: Symbol): Stream[Name] = - imeth.owner.info.decl(imeth.name).tpe match { + private def extensionNames(imeth: Symbol): Stream[Name] = { + val decl = imeth.owner.info.decl(imeth.name) + + // Bridge generation is done at phase `erasure`, but new scopes are only generated + // for the phase after that. So bridges are visible in earlier phases. + // + // `info.member(imeth.name)` filters these out, but we need to use `decl` + // to restrict ourselves to members defined in the current class, so we + // must do the filtering here. + val declTypeNoBridge = decl.filter(sym => !sym.isBridge).tpe + + declTypeNoBridge match { case OverloadedType(_, alts) => val index = alts indexOf imeth assert(index >= 0, alts+" does not contain "+imeth) @@ -55,6 +65,7 @@ abstract class ExtensionMethods extends Transform with TypingTransformers { assert(tpe != NoType, imeth.name+" not found in "+imeth.owner+"'s decls: "+imeth.owner.info.decls) Stream(newTermName("extension$"+imeth.name)) } + } /** Return the extension method that corresponds to given instance method `meth`. */ -- cgit v1.2.3