Re: Link error building a .m tool with clang on Linux

[David Chisnall]

On 4 Jan 2018, at 17:01, Lobron, David <dlobron@akamai.com> wrote:
> 
> ../AkamaiKit.framework/Versions/Current/./libAkamaiKit.so: undefined 
> reference to `vtable for gnustep::libobjc::__objc_class_type_info'

This will happen if you’ve used Objective-C++ and are on a platform that ships 
its stack C++ in a stupid way.  By default on these platforms, libobjc.so 
avoided linking to the C++ standard library and instead provided a libobjcxx.so.

This has confused everyone, so trunk and the upcoming 1.9 release will always 
link to libstdc++.so / libc++.so if this is the only way of getting access to 
the symbols provided by libsupc++ / libcxxrt.

For now, adding -lobjcxx on platforms where libobjcxx.so exists will fix the 
issue (unless you built libobjc without Objective-C++ support, in which case 
you have a different problem).

David