Add test for KT-26638

compiler/testData/diagnostics/tests/annotations/withUseSiteTarget/kt26638.kt

@@ -0,0 +1,21 @@
+// !DIAGNOSTICS: -UNUSED_PARAMETER
+
+// Ann is not repeatable
+annotation class Ann(val x: Int)
+
+@get:Ann(10)
+val a: String
+    @Ann(20) get() = "foo"
+
+@set:Ann(10)
+var b: String = ""
+    @Ann(20) set(value) { field = value }
+
+@setparam:Ann(10)
+var c = " "
+    set(@Ann(20) x) {}
+
+@get:Ann(10)
+<!REPEATED_ANNOTATION!>@get:Ann(20)<!>
+val d: String
+    @Ann(30) <!REPEATED_ANNOTATION!>@Ann(40)<!> get() = "foo"

compiler/testData/diagnostics/tests/annotations/withUseSiteTarget/kt26638.txt

@@ -0,0 +1,11 @@
+package
+
+@setparam:Ann(x = 20) @setparam:Ann(x = 10) public var a: kotlin.String
+
+public final annotation class Ann : kotlin.Annotation {
+    public constructor Ann(/*0*/ x: kotlin.Int)
+    public final val x: kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}