False "dead code" warning caused by repeated parameters

[scabug]

% cat S.scala
object O { def foo(xs: Int*) { }; foo(Nil: _*) }
% /usr/local/scala-2.9.2/bin/scalac -Ywarn-dead-code S.scala
S.scala:1: warning: dead code following this construct
object O { def foo(xs: Int*) { }; foo(Nil: _*) }
                                         ^
one warning found

I checked and the same bug is present in 2.10.0-M7.

Note that -Ywarn-dead-code is part of -Xlint.

[scabug]

Imported From: https://issues.scala-lang.org/browse/SI-6339?orig=1
Reporter: @SethTisue
Affected Versions: 2.9.2, 2.10.0-M7

[scabug]

@paulp said:
The branch I point at in #6338 also takes warn-dead-code out of -Xlint.