An open source project I maintain, https://github.com/http4s/rho, is no longer able to properly resolve necessary implicits when using scalac 2.11.8 which had previously worked with scalac 2.11.7. Bisecting scalac shows that commit scala/scala@5db2d831a79f6ea3 is the cause and reverting that commit fixes the build.

I haven't made a reduced example yet, and rho's use of implicits is extensive so it might be a challenge. Its simple to reproduce the error: clone the rho library and attempt to compile the whole project:

$ git clone https://github.com/http4s/rho
$ cd rho
$ sbt
> ++2.11.8
> clean
> compile

(Notes that the build file currently uses scalac 2.11.7 so the compiler version must be changed)