diff --git a/library/src/dotty/DottyPredef.scala b/library/src/dotty/DottyPredef.scala
index 75bc60988b42..09facf4b31f8 100644
--- a/library/src/dotty/DottyPredef.scala
+++ b/library/src/dotty/DottyPredef.scala
@@ -24,4 +24,18 @@ object DottyPredef {
    *  `discardForView` from two to one.
    */
   abstract class ImplicitConverter[-T, +U] extends Function1[T, U]
+
+  @inline final def assert(assertion: Boolean, message: => Any): Unit = {
+    if (!assertion)
+      assertFail(message)
+  }
+
+  @inline final def assert(assertion: Boolean): Unit = {
+    if (!assertion)
+      assertFail()
+  }
+
+  final def assertFail(): Unit = throw new java.lang.AssertionError("assertion failed")
+  final def assertFail(message: => Any): Unit = throw new java.lang.AssertionError("assertion failed: " + message)
+
 }
diff --git a/tests/neg/nopredef.scala b/tests/neg/nopredef.scala
index 0079be41ee10..6acf84600978 100644
--- a/tests/neg/nopredef.scala
+++ b/tests/neg/nopredef.scala
@@ -1,4 +1,5 @@
 import Predef.{assert => _}
+import dotty.DottyPredef.{assert => _}
 
 object Test {
   assert("asdf" == "asdf") // error: not found assert