Re: gcc dual abi

[maya%netbsd.org@localhost]

On Sat, Oct 27, 2018 at 08:31:41PM -0400, Greg Troxel wrote:
> So if on an old system -- let's say NetBSD 5 or 6 -- I build gcc5, and
> then use that to build everything, should that work?  Absent
> intentionally setting _GLIBCXX_USE_CXX11_ABI, would I be getting the new
> C++11-compliant ABI or the old, compatible but not compliant ABI?

I'm not sure if you can expect that to work at all, even not going into
the question of dual ABI. Some possible problems I can think of:
- I don't know if the libstdc++ patch will work on netbsd-5
- libstdc++ will disable parts of its functionality when it detects some
  missing functions, and I think the result for netbsd-6 wasn't
  functional, but perhaps newer versions of GCC have the fix I was
  looking at the time.