C++11 code in the gcc 10 branch

[Gerald Pfeifer]

On Mon, 21 Dec 2020, FX via Gcc wrote:
> I’m trying to bootstrap a GCC 10 compiler on macOS with clang, and I am 
> getting errors in stage 1, because there is C++11 code that is rejected 
> by clang (because the bootstrap involves compiling stage 1 with 
> -std=gnu++98, online on master (see top-level configure.ac).

I got reports from users, too (for FreeBSD with clang as system 
compiler), and have them test this patch which looks fine so far.

> These errors are not seen, I believe, when GCC is the bootstrap 
> compiler, because GCC will issue a warning instead of an error (as 
> clang does).
> 
> One place with such issue is in aarch64-builtins.c, which contains a 
> C++11 constructor. I can fix it with this:

When are you going to apply your fix that Richard S. approved on the
21st?

Gerald