Fix scala#9166: Harden check for values in patterns based on class inheritance info

Author: liufengyun

compiler/src/dotty/tools/dotc/typer/Typer.scala

@@ -3808,7 +3808,10 @@ class Typer extends Namer
               mapOver(tp)
         }
 
-        if tree.symbol.isOneOf(Module | Enum)
+        val sym = tree.symbol
+
+        // Is it certain that a value of `tree.tpe` is never a subtype of `pt`
+        if (!sym.info.classSymbol.isNumericValueClass || !pt.classSymbol.isNumericValueClass)
            && !(tree.tpe frozen_<:< pt) // fast track
            && !(tree.tpe frozen_<:< approx(pt))
         then

tests/neg/i9166.scala

@@ -0,0 +1,6 @@
+object UnitTest extends App {
+  def foo(m: Unit) = m match {
+    case runtime.BoxedUnit.UNIT => println("ok") // error
+  }
+  foo(())
+}