diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/compiler/scala/tools/nsc/transform/Erasure.scala | 13 |
1 files changed, 11 insertions, 2 deletions
diff --git a/src/compiler/scala/tools/nsc/transform/Erasure.scala b/src/compiler/scala/tools/nsc/transform/Erasure.scala index 915aba63db..2cf3d06866 100644 --- a/src/compiler/scala/tools/nsc/transform/Erasure.scala +++ b/src/compiler/scala/tools/nsc/transform/Erasure.scala @@ -1022,9 +1022,18 @@ abstract class Erasure extends AddInterfaces Apply(Select(qual, cmpOp), List(gen.mkAttributedQualifier(targ.tpe))) } case RefinedType(parents, decls) if (parents.length >= 2) => - gen.evalOnce(qual, currentOwner, unit) { q => + // Optimization: don't generate isInstanceOf tests if the static type + // conforms, because it always succeeds. (Or at least it had better.) + // At this writing the pattern matcher generates some instance tests + // involving intersections where at least one parent is statically known true. + // That needs fixing, but filtering the parents here adds an additional + // level of robustness (in addition to the short term fix.) + val parentTests = parents filterNot (qual.tpe <:< _) + + if (parentTests.isEmpty) Literal(Constant(true)) + else gen.evalOnce(qual, currentOwner, unit) { q => atPos(tree.pos) { - parents map mkIsInstanceOf(q) reduceRight gen.mkAnd + parentTests map mkIsInstanceOf(q) reduceRight gen.mkAnd } } case _ => |