Sync with Scala Native 0.4.9 (#24)

Author: WojciechMazur

build.sbt

@@ -51,7 +51,7 @@ val cliAssemblyJarName = settingKey[String]("Name of created assembly jar")
 inThisBuild(
   Def.settings(
     organization := "org.scala-native",
-    scalaNativeVersion := "0.4.8",
+    scalaNativeVersion := "0.4.9",
     version := scalaNativeVersion.value,
     scalaVersion := crossScalaVersions212.last,
     crossScalaVersions := publishScalaVersions,

cli/src/main/scala/scala/scalanative/cli/options/NativeConfigOptions.scala

@@ -16,6 +16,7 @@ case class NativeConfigOptions(
     dump: Boolean = false,
     noOptimize: Boolean = false,
     embedResources: Boolean = false,
+    incrementalCompilation: Boolean = false,
     ltp: List[String] = List.empty,
     linkingOption: List[String] = List.empty,
     compileOption: List[String] = List.empty,
@@ -97,6 +98,17 @@ object NativeConfigOptions {
         c.copy(nativeConfig = c.nativeConfig.copy(embedResources = true))
       )
       .text("Shall resources file be embeded into executable? [false]")
+    parser
+      .opt[Unit]("incremental-compilation")
+      .optional()
+      .action((x, c) =>
+        c.copy(nativeConfig =
+          c.nativeConfig.copy(incrementalCompilation = true)
+        )
+      )
+      .text(
+        "Shall use incremental compilation mode for builds? (experimental) [false]"
+      )
     parser
       .opt[String]("ltp")
       .valueName("<keystring=value>")

cli/src/main/scala/scala/scalanative/cli/utils/ConfigConverter.scala

@@ -72,6 +72,7 @@ object ConfigConverter {
       .withLinkingOptions(options.nativeConfig.linkingOption)
       .withLinktimeProperties(ltp)
       .withBuildTarget(options.nativeConfig.buildTarget)
+      .withIncrementalCompilation(options.nativeConfig.incrementalCompilation)
       .withOptimizerConfig(generateOptimizerConfig(options.optimizerConifg))
   }