Rare combination of mixing traits with annotated values causes an erroneous "inherits conflicting members" error in 2.10

[DaniRey]

Mixing two traits, which contain a val annotated with @deprecated and using .stripMargin on the message (i.e. `@deprecated(message = "a".stripMargin, since = "a 1.0") in a separate compilation, causes an erroneous "inherits conflicting members" error in 2.10

sbt:DeprecatedValueBug> it:compile 
[info] Updating ... 
[info] Done updating. 
[info] Compiling 2 Scala sources to ....\DeprecatedValueBug\target\scala-2.10\classes ... 
[info] Done compiling. 
[info] Compiling 1 Scala source to ....\DeprecatedValueBug\target\scala-2.10\it-classes ... 
[error] .....\DeprecatedValueBug\src\it\scala\Use.scala:1:7: class Use inherits conflicting members: [error] value x in trait A of type String and 
[error] value x in trait B of type String 
[error] (Note: this can be resolved by declaring an override in class Use.) 
[error] class Use extends A with B { [error] ^ 
[error] one error found 
[error] (IntegrationTest / compileIncremental) Compilation failed 
[error] Total time: 1 s, completed 01.10.2018 23:11:52

Neither of the traits contains value x.

trait A {
  @deprecated(
    """
      |a
    """.stripMargin, "DepecatedValueBug")
  val a: String = "a"
}

trait B {
  @deprecated(
    """
      |b
      |"""".stripMargin, "DepecatedValueBug")
  val b: String = "b"
}

class Use extends A with B {

}

The error only occurs in Scala 2.10. https://github.com/DaniRey/DeprecatedValueBug contains the code needed to reproduce the issue.

[SethTisue]

thanks Dani! since this bug is 2.10-only, I'm closing it, but it's good to have the report here for future searchers to find. 2.10 will remain in use for some time yet to come.

[SethTisue]

(not sure if related to #261)