diff options
Diffstat (limited to 'compiler/src/dotty/tools/dotc/typer/Typer.scala')
| -rw-r--r-- | compiler/src/dotty/tools/dotc/typer/Typer.scala | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/compiler/src/dotty/tools/dotc/typer/Typer.scala b/compiler/src/dotty/tools/dotc/typer/Typer.scala index b70a51d1e..a053a0b0d 100644 --- a/compiler/src/dotty/tools/dotc/typer/Typer.scala +++ b/compiler/src/dotty/tools/dotc/typer/Typer.scala @@ -1173,6 +1173,7 @@ class Typer extends Namer with TypeAssigner with Applications with Implicits wit if (sym.is(Inline, butNot = DeferredOrParamAccessor)) checkInlineConformant(rhs1, em"right-hand side of inline $sym") patchIfLazy(vdef1) + patchFinalVals(vdef1) vdef1 } @@ -1185,6 +1186,27 @@ class Typer extends Namer with TypeAssigner with Applications with Implicits wit patch(Position(toUntyped(vdef).pos.start), "@volatile ") } + /** Adds inline to final vals with idempotent rhs + * + * duplicating scalac behavior: for final vals that have rhs as constant, we do not create a field + * and instead return the value. This seemingly minor optimization has huge effect on initialization + * order and the values that can be observed during superconstructor call + * + * see remark about idempotency in PostTyper#normalizeTree + */ + private def patchFinalVals(vdef: ValDef)(implicit ctx: Context): Unit = { + def isFinalInlinableVal(sym: Symbol): Boolean = { + sym.is(Final, butNot = Mutable) && + isIdempotentExpr(vdef.rhs) /* && + ctx.scala2Mode (stay compatible with Scala2 for now) */ + } + val sym = vdef.symbol + sym.info match { + case info: ConstantType if isFinalInlinableVal(sym) && !ctx.settings.YnoInline.value => sym.setFlag(Inline) + case _ => + } + } + def typedDefDef(ddef: untpd.DefDef, sym: Symbol)(implicit ctx: Context) = track("typedDefDef") { val DefDef(name, tparams, vparamss, tpt, _) = ddef completeAnnotations(ddef, sym) |