diff --git a/compiler/src/dotty/tools/dotc/transform/GenericSignatures.scala b/compiler/src/dotty/tools/dotc/transform/GenericSignatures.scala
index de558d2494b3..e71460b806e3 100644
--- a/compiler/src/dotty/tools/dotc/transform/GenericSignatures.scala
+++ b/compiler/src/dotty/tools/dotc/transform/GenericSignatures.scala
@@ -317,7 +317,7 @@ object GenericSignatures {
       val psyms = parents map (_.typeSymbol)
       if (psyms contains defn.ArrayClass) {
         // treat arrays specially
-        defn.ArrayType.appliedTo(intersectionDominator(parents.filter(_.typeSymbol == defn.ArrayClass).map(t => t.typeParams.head.paramInfo)))
+        defn.ArrayType.appliedTo(intersectionDominator(parents.filter(_.typeSymbol == defn.ArrayClass).map(t => t.argInfos.head)))
       } else {
         // implement new spec for erasure of refined types.
         def isUnshadowed(psym: Symbol) =
diff --git a/tests/generic-java-signatures/i4248.check b/tests/generic-java-signatures/i4248.check
new file mode 100644
index 000000000000..fbf53ce0227b
--- /dev/null
+++ b/tests/generic-java-signatures/i4248.check
@@ -0,0 +1 @@
+public <U> void Foo$.foo(int[])
\ No newline at end of file
diff --git a/tests/generic-java-signatures/i4248.scala b/tests/generic-java-signatures/i4248.scala
new file mode 100644
index 000000000000..91b34cd41a52
--- /dev/null
+++ b/tests/generic-java-signatures/i4248.scala
@@ -0,0 +1,10 @@
+object Foo {
+  def foo[U](u: Array[Int] & Array[U]): Unit = ()
+}
+
+object Test {
+  def main(args: Array[String]): Unit = {
+    val f1 = Foo.getClass.getMethods.find(_.getName.endsWith("foo")).get
+    println(f1.toGenericString)
+  }
+}