Fix compilation errors with libstdc++v3 for AVR target and allow --enable-libstdcxx

[Jonathan Wakely]

On 10/11/16 13:39 -0200, Felipe Magno de Almeida wrote:
>Hello,
>
>Sorry for top-posting, but this is a ping for the attached patch.
>
>The patch doesn't seem to have been applied nor refused. So I'm
>pinging to see if I need to change something? I already have a
>copyright assignment now.

Sorry for the delay. It's on my list to deal with. I've been on
vacation and then busy at C++ standards meeting.


>I'm attaching a updated patch that doesn't conflict in the Changelog
>file.

Don't include ChangeLogs in the patch, just include the ChangeLog
content in the email, so there's no problem with the ChangeLog churn
making the patch fail :-)

I'll deal with it next week when I'm back home.