diff --git a/compiler/src/dotty/tools/dotc/typer/ProtoTypes.scala b/compiler/src/dotty/tools/dotc/typer/ProtoTypes.scala
index 32240e91da77..6b72f3a8b56e 100644
--- a/compiler/src/dotty/tools/dotc/typer/ProtoTypes.scala
+++ b/compiler/src/dotty/tools/dotc/typer/ProtoTypes.scala
@@ -117,7 +117,7 @@ object ProtoTypes {
     def constrainResult(meth: Symbol, mt: Type, pt: Type)(using Context): Boolean =
       if (Inlines.isInlineable(meth)) {
         // Stricter behaviour in 3.4+: do not apply `wildApprox` to non-transparent inlines
-        if (Feature.sourceVersion.isAtLeast(SourceVersion.future)) {
+        if (Feature.sourceVersion.isAtLeast(SourceVersion.`3.4`)) {
           if (meth.is(Transparent)) {
             constrainResult(mt, wildApprox(pt))
             // do not constrain the result type of transparent inline methods
diff --git a/tests/neg-macros/i18174.check b/tests/neg-macros/i18174.check
new file mode 100644
index 000000000000..1f4396d6b5ca
--- /dev/null
+++ b/tests/neg-macros/i18174.check
@@ -0,0 +1,12 @@
+-- [E172] Type Error: tests/neg-macros/i18174.scala:27:33 --------------------------------------------------------------
+27 |  (charClassIntersection.rep() | classItem.rep()) // error
+   |                                 ^^^^^^^^^^^^^^^
+   |No given instance of type pkg.Implicits.Repeater[pkg.RegexTree, V] was found.
+   |I found:
+   |
+   |    pkg.Implicits.Repeater.GenericRepeaterImplicit[T]
+   |
+   |But method GenericRepeaterImplicit in object Repeater does not match type pkg.Implicits.Repeater[pkg.RegexTree, V]
+   |
+   |where:    V is a type variable with constraint <: Seq[pkg.CharClassIntersection]
+   |.
diff --git a/tests/neg-macros/i18174.scala b/tests/neg-macros/i18174.scala
new file mode 100644
index 000000000000..8bb5ffd51a3f
--- /dev/null
+++ b/tests/neg-macros/i18174.scala
@@ -0,0 +1,27 @@
+// does not compile anymore in Scala 3.4+
+package pkg
+
+import scala.language.`3.4`
+
+trait P[+T]
+
+extension [T](inline parse0: P[T])
+  inline def | [V >: T](inline other: P[V]): P[V] = ???
+
+extension [T](inline parse0: => P[T])
+  inline def rep[V](inline min: Int = 0)(using repeater: Implicits.Repeater[T, V]): P[V] = ???
+
+object Implicits:
+  trait Repeater[-T, R]
+  object Repeater:
+    implicit def GenericRepeaterImplicit[T]: Repeater[T, Seq[T]] = ???
+
+sealed trait RegexTree
+abstract class Node extends RegexTree
+class CharClassIntersection() extends Node
+
+def classItem: P[RegexTree] = ???
+def charClassIntersection: P[CharClassIntersection] = ???
+
+def x =
+  (charClassIntersection.rep() | classItem.rep()) // error
diff --git a/tests/pos-macros/i18123.scala b/tests/pos-macros/i18123.scala
index 714850004d2c..d9127a918ee8 100644
--- a/tests/pos-macros/i18123.scala
+++ b/tests/pos-macros/i18123.scala
@@ -1,6 +1,8 @@
 // may not compile anymore in Scala 3.4+
 package pkg
 
+import scala.language.`3.3`
+
 trait P[+T]
 
 extension [T](inline parse0: P[T])