diff --git a/internal/compiler-bridge/src/main/scala/xsbt/Dependency.scala b/internal/compiler-bridge/src/main/scala/xsbt/Dependency.scala
index 20ce91c9d6..1bad94f944 100644
--- a/internal/compiler-bridge/src/main/scala/xsbt/Dependency.scala
+++ b/internal/compiler-bridge/src/main/scala/xsbt/Dependency.scala
@@ -92,16 +92,21 @@ final class Dependency(val global: CallbackGlobal) extends LocateClassFile with
     }
 
     // Define processor reusing `processDependency` definition
-    val memberRef = processDependency(DependencyByMemberRef) _
-    val inheritance = processDependency(DependencyByInheritance) _
-    val localInheritance = processDependency(LocalDependencyByInheritance) _
+    val memberRef = processDependency(DependencyByMemberRef, false) _
+    val inheritance = processDependency(DependencyByInheritance, true) _
+    val localInheritance = processDependency(LocalDependencyByInheritance, true) _
+
+    @deprecated("Use processDependency that takes allowLocal.", "1.1.0")
+    def processDependency(context: DependencyContext)(dep: ClassDependency): Unit =
+      processDependency(context, true)(dep)
 
     /*
      * Handles dependency on given symbol by trying to figure out if represents a term
      * that is coming from either source code (not necessarily compiled in this compilation
      * run) or from class file and calls respective callback method.
      */
-    def processDependency(context: DependencyContext)(dep: ClassDependency): Unit = {
+    def processDependency(context: DependencyContext, allowLocal: Boolean)(
+        dep: ClassDependency): Unit = {
       val fromClassName = classNameAsString(dep.from)
 
       def binaryDependency(file: File, binaryClassName: String) =
@@ -133,11 +138,12 @@ final class Dependency(val global: CallbackGlobal) extends LocateClassFile with
           case None =>
             debuglog(Feedback.noOriginFileForExternalSymbol(dep.to))
         }
-      } else if (onSource.file != sourceFile) {
-        // Dependency is internal -- but from other file / compilation unit
+      } else if (onSource.file != sourceFile || allowLocal) {
+        // We cannot ignore dependencies coming from the same source file because
+        // the dependency info needs to propagate. See source-dependencies/trait-trait-211.
         val onClassName = classNameAsString(dep.to)
         callback.classDependency(onClassName, fromClassName, context)
-      } else () // Comes from the same file, ignore
+      }
     }
   }
 
@@ -227,7 +233,6 @@ final class Dependency(val global: CallbackGlobal) extends LocateClassFile with
       val depClass = enclOrModuleClass(dep)
       val dependency = ClassDependency(fromClass, depClass)
       if (!cache.contains(dependency) &&
-          fromClass.associatedFile != depClass.associatedFile &&
           !depClass.isRefinementClass) {
         process(dependency)
         cache.add(dependency)
diff --git a/internal/zinc-core/src/main/scala/sbt/internal/inc/Relations.scala b/internal/zinc-core/src/main/scala/sbt/internal/inc/Relations.scala
index 16318212f6..6f78eb1524 100644
--- a/internal/zinc-core/src/main/scala/sbt/internal/inc/Relations.scala
+++ b/internal/zinc-core/src/main/scala/sbt/internal/inc/Relations.scala
@@ -275,6 +275,7 @@ object Relations {
       case o: ClassDependencies => internal == o.internal && external == o.external
       case _                    => false
     }
+    override def toString: String = s"ClassDependencies(internal = $internal, external = $external)"
 
     override def hashCode = (internal, external).hashCode
   }
@@ -661,26 +662,23 @@ private class MRelationsNameHashing(
   override def hashCode =
     (srcProd :: libraryDep :: libraryClassName :: memberRef :: inheritance :: classes :: Nil).hashCode
 
-  override def toString = (
-    """
+  override def toString: String = {
+    val internalDepsStr = (internalDependencies.dependencies map {
+      case (k, vs) => k + " " + relation_s(vs)
+    }).mkString("\n    ", "\n    ", "")
+    val externalDepsStr = (externalDependencies.dependencies map {
+      case (k, vs) => k + " " + relation_s(vs)
+    }).mkString("\n    ", "\n    ", "")
+    s"""
     |Relations (with name hashing enabled):
-    |  products: %s
-    |  library deps: %s
-    |  library class names: %s
-    |  class deps: %s
-    |  ext deps: %s
-    |  class names: %s
-    |  used names: %s
-    |  product class names: %s
-    """.trim.stripMargin.format(
-      List(srcProd,
-           libraryDep,
-           libraryClassName,
-           internalClassDep,
-           externalClassDep,
-           classes,
-           names,
-           productClassName) map relation_s: _*)
-  )
-
+    |  products: ${relation_s(srcProd)}
+    |  library deps: ${relation_s(libraryDep)}
+    |  library class names: ${relation_s(libraryClassName)}
+    |  internalDependencies: $internalDepsStr
+    |  externalDependencies: $externalDepsStr
+    |  class names: ${relation_s(classes)}
+    |  used names: ${relation_s(names)}
+    |  product class names: ${relation_s(productClassName)}
+    """.trim.stripMargin
+  }
 }
diff --git a/zinc/src/sbt-test/source-dependencies/patMat-scope/test b/zinc/src/sbt-test/source-dependencies/patMat-scope/test
index 48a933573b..60aa342999 100644
--- a/zinc/src/sbt-test/source-dependencies/patMat-scope/test
+++ b/zinc/src/sbt-test/source-dependencies/patMat-scope/test
@@ -12,9 +12,7 @@ $ sleep 1000
 $ exists target/classes/foo/SealedUsedInPatMatScope.class
 $ exists target/classes/foo/SealedNameUsedInDefaultScope.class
 
-# Default scopes should not change
-$ newer beforeFirstCompilation target/classes/foo/SealedNameUsedInDefaultScope.class
-# But PatMat and direct usage of child should be recompiled
+# PatMat and direct usage of child should be recompiled
 $ newer target/classes/foo/SealedUsedInPatMatScope.class beforeFirstCompilation
 
 # Change type of Sealed
diff --git a/zinc/src/sbt-test/source-dependencies/trait-trait-211/build.json b/zinc/src/sbt-test/source-dependencies/trait-trait-211/build.json
new file mode 100644
index 0000000000..e2b0035d3b
--- /dev/null
+++ b/zinc/src/sbt-test/source-dependencies/trait-trait-211/build.json
@@ -0,0 +1,8 @@
+{
+  "projects": [
+    {
+      "name": "mirtest",
+      "scalaVersion": "2.11.8"
+    }
+  ]
+}
diff --git a/zinc/src/sbt-test/source-dependencies/trait-trait-211/changes/SliceTransforms1.scala b/zinc/src/sbt-test/source-dependencies/trait-trait-211/changes/SliceTransforms1.scala
new file mode 100644
index 0000000000..8004d156a8
--- /dev/null
+++ b/zinc/src/sbt-test/source-dependencies/trait-trait-211/changes/SliceTransforms1.scala
@@ -0,0 +1,12 @@
+package gg
+package table
+
+trait SliceTransforms {
+  def transform: Unit = {
+    // the use site is updated
+    buildNonemptyObjects(0, 1)
+  }
+
+  // add extra parameter here
+  def buildNonemptyObjects(a: Int, b: Int): Unit = ()
+}
diff --git a/zinc/src/sbt-test/source-dependencies/trait-trait-211/mirtest/EvaluatorSpecs.scala b/zinc/src/sbt-test/source-dependencies/trait-trait-211/mirtest/EvaluatorSpecs.scala
new file mode 100644
index 0000000000..32e7b8cf8d
--- /dev/null
+++ b/zinc/src/sbt-test/source-dependencies/trait-trait-211/mirtest/EvaluatorSpecs.scala
@@ -0,0 +1,9 @@
+package xx
+
+import gg.table._
+
+trait EvaluatorSpecification extends EvaluatorTestSupport {
+}
+
+trait EvaluatorTestSupport extends SliceTransforms {
+}
diff --git a/zinc/src/sbt-test/source-dependencies/trait-trait-211/mirtest/Hello.scala b/zinc/src/sbt-test/source-dependencies/trait-trait-211/mirtest/Hello.scala
new file mode 100644
index 0000000000..10e1143812
--- /dev/null
+++ b/zinc/src/sbt-test/source-dependencies/trait-trait-211/mirtest/Hello.scala
@@ -0,0 +1,8 @@
+package xx
+
+object Hello extends App {
+  val consumer = new StringLibSpecs
+  consumer.transform
+}
+
+class StringLibSpecs extends EvaluatorSpecification
diff --git a/zinc/src/sbt-test/source-dependencies/trait-trait-211/mirtest/SliceTransforms.scala b/zinc/src/sbt-test/source-dependencies/trait-trait-211/mirtest/SliceTransforms.scala
new file mode 100644
index 0000000000..fb8c4c462d
--- /dev/null
+++ b/zinc/src/sbt-test/source-dependencies/trait-trait-211/mirtest/SliceTransforms.scala
@@ -0,0 +1,10 @@
+package gg
+package table
+
+trait SliceTransforms {
+  def transform: Unit = {
+    buildNonemptyObjects(0)
+  }
+
+  def buildNonemptyObjects(a: Int): Unit = ()
+}
diff --git a/zinc/src/sbt-test/source-dependencies/trait-trait-211/mirtest/incOptions.properties b/zinc/src/sbt-test/source-dependencies/trait-trait-211/mirtest/incOptions.properties
new file mode 100644
index 0000000000..adfc92c361
--- /dev/null
+++ b/zinc/src/sbt-test/source-dependencies/trait-trait-211/mirtest/incOptions.properties
@@ -0,0 +1 @@
+relationsDebug = true
diff --git a/zinc/src/sbt-test/source-dependencies/trait-trait-211/test b/zinc/src/sbt-test/source-dependencies/trait-trait-211/test
new file mode 100644
index 0000000000..d0fb2c1e75
--- /dev/null
+++ b/zinc/src/sbt-test/source-dependencies/trait-trait-211/test
@@ -0,0 +1,5 @@
+> mirtest/run
+
+## After copying the Good implementation, we should be able to run successfully.
+$ copy-file changes/SliceTransforms1.scala mirtest/SliceTransforms.scala
+> mirtest/run