On 1 February 2017 at 16:20, Marcus Calhoun-Lopez wrote: > Yes, we are talking about the libstdc++ that is shipped with gcc6.
OK. Something that's not entirely clear to me yet is what's the benefit of having clang compile software against gcc's libstdc++ vs. gcc6 compiling it. And what's the relation of all this to the magic -D_GLIBCXX_USE_CXX11_ABI=0 flag. > I should have made clear that a major downside of choice #2 is that it > requires a library dependency on gcc6. Thanks, I missed that. And I agree that this is a bit of a downside. What kind of dependency is that exactly? Is it only a dependency because the port needs to make sure that gcc's libstdc++ is present at the time of compilation or are there some other more hardwired constraints? > That is something that most (the vast majority of?) users will not want. > So perhaps choice #3 or choice #2 with the default variant only for systems > prior to OS X Mavericks? We could certainly limit this to pre-Mavericks systems if that doesn't make things super complicated. The other question is whether we need to have this enabled for all versions of clang or would a single compiler suffice. (I would help if I better understood all consequences and a couple of use cases.) We just have to be careful to make sure that we don't create an even bigger and more incompatible mess :) And we should finally address binary builds for libc++. That would likely solve 99.9% of our C++11-related problems. Mojca
