3 files changed, 43 insertions, 3 deletions
diff --git a/src/compiler/scala/tools/nsc/javac/JavaParsers.scala b/src/compiler/scala/tools/nsc/javac/JavaParsers.scala
index 4d36816853..4d230470c6 100755
--- a/src/compiler/scala/tools/nsc/javac/JavaParsers.scala
+++ b/src/compiler/scala/tools/nsc/javac/JavaParsers.scala
@@ -633,9 +633,29 @@ trait JavaParsers extends JavaScanners {
         Import(Ident(cdef.name.toTermName), List((nme.WILDCARD, null)))
       }
 
-    // create companion object even if it has no statics, so import A._ works; bug #1700
-    def addCompanionObject(statics: List[Tree], cdef: ClassDef): List[Tree] =
-      List(makeCompanionObject(cdef, statics), importCompanionObject(cdef), cdef)
+    // Importing the companion object members cannot be done uncritically: see
+    // ticket #2377 wherein a class contains two static inner classes, each of which
+    // has a static inner class called "Builder" - this results in an ambiguity error
+    // when each performs the import in the enclosing class's scope.
+    //
+    // To address this I moved the import Companion._ inside the class, as the first
+    // statement.  This should work without compromising the enclosing scope, but may (?)
+    // end up suffering from the same issues it does in scala - specifically that this
+    // leaves auxiliary constructors unable to access members of the companion object
+    // as unqualified identifiers.
+    def addCompanionObject(statics: List[Tree], cdef: ClassDef): List[Tree] = {
+      def implWithImport(importStmt: Tree) = {
+        import cdef.impl._
+        treeCopy.Template(cdef.impl, parents, self, importStmt :: body)
+      }
+      // if there are no statics we can use the original cdef, but we always
+      // create the companion so import A._ is not an error (see ticket #1700)
+      val cdefNew =
+        if (statics.isEmpty) cdef
+        else treeCopy.ClassDef(cdef, cdef.mods, cdef.name, cdef.tparams, implWithImport(importCompanionObject(cdef)))
+
+      List(makeCompanionObject(cdefNew, statics), cdefNew)
+    }
 
     def importDecl(): List[Tree] = {
       accept(IMPORT)
diff --git a/test/files/pos/t2377/Q.java b/test/files/pos/t2377/Q.java
new file mode 100644
index 0000000000..ef5b0574a6
--- /dev/null
+++ b/test/files/pos/t2377/Q.java
@@ -0,0 +1,12 @@
+public final class Q {
+  public static final class Stage {
+    public static Builder newBuilder() { return new Builder(); }
+    public static final class Builder { }
+    public Builder toBuilder() { return newBuilder(); }
+  }
+  public static final class WorkUnit {
+    public static Builder newBuilder() { return new Builder(); }
+    public static final class Builder { }
+    public Builder toBuilder() { return newBuilder(); }
+  }
+}
+\ No newline at end of file
diff --git a/test/files/pos/t2377/a.scala b/test/files/pos/t2377/a.scala
new file mode 100644
index 0000000000..5ec58987ff
--- /dev/null
+++ b/test/files/pos/t2377/a.scala
@@ -0,0 +1,8 @@
+import Q._
+
+class Bop(var workUnit: WorkUnit) {
+  def addStages(stageBuilder: Stage.Builder): Unit = {
+    val builder = workUnit.toBuilder
+    ()
+  }
+}
+\ No newline at end of file