diff --git a/main/src/main/scala/sbt/Defaults.scala b/main/src/main/scala/sbt/Defaults.scala
index a275d0d5b..94a72e521 100755
--- a/main/src/main/scala/sbt/Defaults.scala
+++ b/main/src/main/scala/sbt/Defaults.scala
@@ -307,8 +307,13 @@ object Defaults extends BuildCommon {
       if (plugin) scalaBase / ("sbt-" + sbtv) else scalaBase
     }
 
-  def compilersSetting = compilers := Compiler.compilers(scalaInstance.value, classpathOptions.value, javaHome.value,
-    bootIvyConfiguration.value, fileToStore.value, scalaCompilerBridgeSource.value)(appConfiguration.value, streams.value.log)
+  def compilersSetting = compilers := {
+    val compilers = Compiler.compilers(scalaInstance.value, classpathOptions.value, javaHome.value,
+      bootIvyConfiguration.value, fileToStore.value, scalaCompilerBridgeSource.value)(appConfiguration.value, streams.value.log)
+    if (!java.lang.Boolean.getBoolean("sbt.disable.interface.classloader.cache"))
+      compilers.scalac.setClassLoaderCache(state.value.classLoaderCache)
+    compilers
+  }
 
   lazy val configTasks = docTaskSettings(doc) ++ inTask(compile)(compileInputsSettings) ++ configGlobal ++ compileAnalysisSettings ++ Seq(
     compile := compileTask.value,