[RFC] Difference between gcc and g++ drivers

[Joseph Myers]

On Wed, 24 Jun 2015, Andrew Senkevich wrote:

> Can anybody tell something about this difference in drivers?

libstdc++ uses libm - that's probably why g++ links it in by default.

Modern good practice would say that it should only be linked directly into 
a program (should only end up listed in DT_NEEDED) if actually required by 
that program, not if only used indirectly by libstdc++.

> May be needed fix for g++ driver to add also -lmvec if GLIBC version
> >= 2.22 found on configure?

I don't think that's a good idea (even if you depend on the glibc version 
on the target, for which there is various existing precedent, depending on 
*how that version is configured* doesn't seem such a good idea, and 
libmvec is an optional feature only supported at all on x86_64).

-- 
Joseph S. Myers
joseph@codesourcery.com