building from source with libc++

[Chris Jones]

On 19/04/17 09:51, db wrote:
> On 19 Apr 2017, at 10:13, Mojca Miklavec <mojca.miklavec.lists at gmail.com> wrote:
>> https://trac.macports.org/wiki/XcodeVersionInfo
>
> That doesn't tell me anything different from the output I posted. I still don't exactly know which clang version I have.

You cannot really compare the stock LLVM/Clang releases to the Apple 
versions.

First, you need to understand the difference between LLVM and clang. 
LLVM is the base framework for building compilers. Clang is just one 
example of a frontend compiler based on that.

Apple takes a particular version of LLVM, and then builds its own 
compiler on top. So Apples's clang compilers are not exactly comparable 
to the stock versions. The line

Apple LLVM version 5.1 (clang-503.0.40) (based on LLVM 3.4svn)

tells you you have Apples 503.0.40 clang compiler, based on Apple's LLVM 
5.1, which in turn was born from the orginal LLVM code based 'at some 
point' around the 3.4 release... Thats as good as it gets.

LLVM (or clang) 3.4 is quite old. If you are looking to install a newer 
clang compiler via macports, I would start with something like the clang 
3.9 or 4.0 port (4.0 is quite new, so maybe some ports might have issues 
with it more than 3.9).

Chris

>
>> You would run into problems if you installed/built existing ports against libstdc++ and want to build everything against libc++ from now on. In that case you should start from scratch and follow migration instructions.
>
> I already reinstalled everything from scratch with libc++.
>