Imported From: https://issues.scala-lang.org/browse/SI-10021?orig=1
Reporter: @Atry
Affected Versions: 2.11.8, 2.12.0
Duplicates #6714

@SethTisue said:
This may well be a bug, but it seems like such ill-advised code (strange signature for apply, implicit of type Int) that it's hard to imagine it getting attention if this is the only way to trigger it.

@Atry said (edited on Nov 8, 2016 1:49:08 AM UTC):
Another example

Welcome to Scala 2.11.8 (Java HotSpot(TM) 64-Bit Server VM, Java 1.8.0_102).
Type in expressions for evaluation. Or try :help.

scala> object A {
     |   def apply[A](i: A)(implicit ev: Ordering[Int]): Int = 100
     |   def update[A](i: A, value: Int): Unit = print(s"i=$i value=$value")
     | }
defined object A

scala> A(5) += 20
i=scala.math.Ordering$Int$@121314f7 value=120

@som-snytt said:
I took a look the other day and wasn't sure how the expansion should proceed.

A(5) = A(5) + 42
A(5)(ev) = A(5)(ev) + 42
A.apply(5).update(ev, A(5)(ev) + 42)

The apply(5) seems to be elided when it should error; I'm just reading off the scrap of paper, too beset with the ague to think about it.