From e5e691ea2dd53abb64306b91bf172aaa8e2e6b9c Mon Sep 17 00:00:00 2001 From: Guillaume Martres Date: Sat, 11 Mar 2017 16:19:31 +0100 Subject: Fix overriding a Java method with varargs If A method like: override def foo(x: Object*) overrides a Java method, it needs to be rewritten as: def foo(x: Seq[Object]) override def foo(x: Array[Object]): Object = foo(Predef.wrapRefArray(x)) This should be handled by ElimRepeated but there were two bugs: - `addVarArgsBridge` was called at phase `thisTransformer.next`, this is too late to create the bridge since `T*` has already been rewritten as `Seq[T]` - The original method symbol needs to have the `override` flag dropped, since it doesn't override anything. Furthermore, RefChecks had to be moved after ElimRepeated, otherwise the testcase would fail the overriding checks. --- compiler/src/dotty/tools/dotc/Compiler.scala | 4 ++-- compiler/src/dotty/tools/dotc/transform/ElimRepeated.scala | 9 +++++++-- compiler/src/dotty/tools/dotc/typer/RefChecks.scala | 3 +++ 3 files changed, 12 insertions(+), 4 deletions(-) (limited to 'compiler/src') diff --git a/compiler/src/dotty/tools/dotc/Compiler.scala b/compiler/src/dotty/tools/dotc/Compiler.scala index 1d319242b..f413fc902 100644 --- a/compiler/src/dotty/tools/dotc/Compiler.scala +++ b/compiler/src/dotty/tools/dotc/Compiler.scala @@ -48,9 +48,9 @@ class Compiler { List(new Pickler), // Generate TASTY info List(new FirstTransform, // Some transformations to put trees into a canonical form new CheckReentrant), // Internal use only: Check that compiled program has no data races involving global vars - List(new RefChecks, // Various checks mostly related to abstract members and overriding - new CheckStatic, // Check restrictions that apply to @static members + List(new CheckStatic, // Check restrictions that apply to @static members new ElimRepeated, // Rewrite vararg parameters and arguments + new RefChecks, // Various checks mostly related to abstract members and overriding new NormalizeFlags, // Rewrite some definition flags new ExtensionMethods, // Expand methods of value classes with extension methods new ExpandSAMs, // Expand single abstract method closures to anonymous classes diff --git a/compiler/src/dotty/tools/dotc/transform/ElimRepeated.scala b/compiler/src/dotty/tools/dotc/transform/ElimRepeated.scala index 258b7f234..e67b3f114 100644 --- a/compiler/src/dotty/tools/dotc/transform/ElimRepeated.scala +++ b/compiler/src/dotty/tools/dotc/transform/ElimRepeated.scala @@ -95,8 +95,8 @@ class ElimRepeated extends MiniPhaseTransform with InfoTransformer with Annotati assert(ctx.phase == thisTransformer) def overridesJava = tree.symbol.allOverriddenSymbols.exists(_ is JavaDefined) if (tree.symbol.info.isVarArgsMethod && overridesJava) - addVarArgsBridge(tree)(ctx.withPhase(thisTransformer.next)) - else + addVarArgsBridge(tree) + else tree } @@ -120,6 +120,11 @@ class ElimRepeated extends MiniPhaseTransform with InfoTransformer with Annotati .appliedToArgs(vrefs :+ TreeGen.wrapArray(varArgRef, elemtp)) .appliedToArgss(vrefss1) }) + + // Drop the override flag on the user-written method, only the added bridge + // is a real override. + original.copySymDenotation(initFlags = original.flags &~ Override).installAfter(thisTransformer) + Thicket(ddef, bridgeDef) } diff --git a/compiler/src/dotty/tools/dotc/typer/RefChecks.scala b/compiler/src/dotty/tools/dotc/typer/RefChecks.scala index 23d05e087..e8ff7d572 100644 --- a/compiler/src/dotty/tools/dotc/typer/RefChecks.scala +++ b/compiler/src/dotty/tools/dotc/typer/RefChecks.scala @@ -766,6 +766,9 @@ class RefChecks extends MiniPhase { thisTransformer => override def phaseName: String = "refchecks" + // Needs to run after ElimRepeated for override checks involving varargs methods + override def runsAfter = Set(classOf[ElimRepeated]) + val treeTransform = new Transform(NoLevelInfo) class Transform(currentLevel: RefChecks.OptLevelInfo = RefChecks.NoLevelInfo) extends TreeTransform { -- cgit v1.2.3 From 568b1e71d3767827e4a61cd93736ae3b318a6dce Mon Sep 17 00:00:00 2001 From: Guillaume Martres Date: Sun, 12 Mar 2017 16:18:37 +0100 Subject: ElimRepeated: Do not use installAfter This was a mistake introduced in the previous commit, installAfter is only safe to use in `IdentityDenotTransformer` phases, otherwise it means that the phase denotation transformer is not run at all for this particular denotation, this caused Ycheck to fail. --- .../dotty/tools/dotc/transform/ElimRepeated.scala | 20 ++++++++++++++------ 1 file changed, 14 insertions(+), 6 deletions(-) (limited to 'compiler/src') diff --git a/compiler/src/dotty/tools/dotc/transform/ElimRepeated.scala b/compiler/src/dotty/tools/dotc/transform/ElimRepeated.scala index e67b3f114..d955628e3 100644 --- a/compiler/src/dotty/tools/dotc/transform/ElimRepeated.scala +++ b/compiler/src/dotty/tools/dotc/transform/ElimRepeated.scala @@ -32,8 +32,21 @@ class ElimRepeated extends MiniPhaseTransform with InfoTransformer with Annotati def transformInfo(tp: Type, sym: Symbol)(implicit ctx: Context): Type = elimRepeated(tp) + + override def transform(ref: SingleDenotation)(implicit ctx: Context): SingleDenotation = + super.transform(ref) match { + case ref1: SymDenotation if (ref1 ne ref) && overridesJava(ref1.symbol) => + // This method won't override the corresponding Java method at the end of this phase, + // only the bridge added by `addVarArgsBridge` will. + ref1.copySymDenotation(initFlags = ref1.flags &~ Override) + case ref1 => + ref1 + } + override def mayChange(sym: Symbol)(implicit ctx: Context): Boolean = sym is Method + private def overridesJava(sym: Symbol)(implicit ctx: Context) = sym.allOverriddenSymbols.exists(_ is JavaDefined) + private def elimRepeated(tp: Type)(implicit ctx: Context): Type = tp.stripTypeVar match { case tp @ MethodType(paramNames, paramTypes) => val resultType1 = elimRepeated(tp.resultType) @@ -93,8 +106,7 @@ class ElimRepeated extends MiniPhaseTransform with InfoTransformer with Annotati */ override def transformDefDef(tree: DefDef)(implicit ctx: Context, info: TransformerInfo): Tree = { assert(ctx.phase == thisTransformer) - def overridesJava = tree.symbol.allOverriddenSymbols.exists(_ is JavaDefined) - if (tree.symbol.info.isVarArgsMethod && overridesJava) + if (tree.symbol.info.isVarArgsMethod && overridesJava(tree.symbol)) addVarArgsBridge(tree) else tree @@ -121,10 +133,6 @@ class ElimRepeated extends MiniPhaseTransform with InfoTransformer with Annotati .appliedToArgss(vrefss1) }) - // Drop the override flag on the user-written method, only the added bridge - // is a real override. - original.copySymDenotation(initFlags = original.flags &~ Override).installAfter(thisTransformer) - Thicket(ddef, bridgeDef) } -- cgit v1.2.3