Merge pull request #1408 from Duhemm/fix-again-1237

Never inspect twice the same macro application, fix (again) #1237

compile/interface/src/main/scala/xsbt/ExtractUsedNames.scala

@@ -56,12 +56,12 @@ class ExtractUsedNames[GlobalType <: CallbackGlobal](val global: GlobalType) ext
 
     def handleTreeNode(node: Tree): Unit = {
       def handleMacroExpansion(original: Tree): Unit = {
-        // Some macros seem to have themselves registered as original tree.
-        // In this case, we only need to handle the children of the original tree,
-        // because we already handled the expanded tree.
+        // Some macros seem to be their own orignal tree, or appear in the children of their
+        // original tree. To prevent infinite loops, we need to filter out nodes that we already
+        // handled.
+        // This is only relevant for Scala 2.10.4
         // See https://issues.scala-lang.org/browse/SI-8486
-        if (original == node) original.children.foreach(handleTreeNode)
-        else original.foreach(handleTreeNode)
+        original.filter(_ ne node).foreach(handleTreeNode)
       }
 
       def handleClassicTreeNode(node: Tree): Unit = node match {

sbt/src/sbt-test/source-dependencies/macro-arg-dep-stackoverflow/macro-client/Client.scala

@@ -0,0 +1,6 @@
+package macros
+
+object Client {
+  val a = 1
+  def test = Foo.bar(a)
+}

sbt/src/sbt-test/source-dependencies/macro-arg-dep-stackoverflow/macro-provider/Foo.scala

@@ -0,0 +1,9 @@
+package macros
+
+import scala.language.experimental.macros
+import scala.reflect.macros.Context
+
+object Foo {
+  def bar(a: Any): Any = macro impl
+  def impl(c: Context)(a: c.Expr[Any]): c.Expr[Any] = a
+}

sbt/src/sbt-test/source-dependencies/macro-arg-dep-stackoverflow/project/build.scala

@@ -0,0 +1,29 @@
+import sbt._
+import Keys._
+
+object build extends Build {
+	val defaultSettings = Seq(
+		libraryDependencies <+= scalaVersion("org.scala-lang" % "scala-reflect" % _ ),
+		incOptions := incOptions.value.withNameHashing(true)
+	)
+
+	lazy val root = Project(
+	   base = file("."),
+	   id = "macro",
+	   aggregate = Seq(macroProvider, macroClient),
+	   settings = Defaults.defaultSettings ++ defaultSettings
+	)
+
+	lazy val macroProvider = Project(
+	   base = file("macro-provider"),
+	   id = "macro-provider",
+	   settings = Defaults.defaultSettings ++ defaultSettings
+	)
+
+	lazy val macroClient = Project(
+	   base = file("macro-client"),
+	   id = "macro-client",
+	   dependencies = Seq(macroProvider),
+	   settings = Defaults.defaultSettings ++ defaultSettings
+	)
+}

sbt/src/sbt-test/source-dependencies/macro-arg-dep-stackoverflow/test

@@ -0,0 +1,2 @@
+# We only want to make sure we can compile this without stack overflow
+> compile