1 files changed, 9 insertions, 2 deletions
diff --git a/core/src/mill/util/ClassLoader.scala b/core/src/mill/util/ClassLoader.scala
index a1b42158..b53150c2 100644
--- a/core/src/mill/util/ClassLoader.scala
+++ b/core/src/mill/util/ClassLoader.scala
@@ -5,7 +5,9 @@ import java.net.{URL, URLClassLoader}
 import io.github.retronym.java9rtexport.Export
 
 object ClassLoader {
-  def create(urls: Seq[URL], parent: java.lang.ClassLoader): URLClassLoader = {
+  def create(urls: Seq[URL],
+             parent: java.lang.ClassLoader)
+            (implicit ctx: Ctx.Home): URLClassLoader = {
     val cl = new URLClassLoader(urls.toArray, parent)
     if (!ammonite.util.Util.java9OrAbove) return cl
     try {
@@ -13,7 +15,12 @@ object ClassLoader {
       cl
     } catch {
       case _: ClassNotFoundException =>
-        new URLClassLoader((urls ++ Some(Export.export().toURI.toURL)).toArray, parent)
+        val path = ctx.home
+        val rtFile = new java.io.File(path.toIO, s"rt-${System.getProperty("java.version")}.jar")
+        if (!rtFile.exists) {
+          java.nio.file.Files.copy(Export.export().toPath, rtFile.toPath)
+        }
+        new URLClassLoader((urls ++ Some(rtFile.toURI.toURL)).toArray, parent)
     }
   }
 }