Undefined symbols for architecture x86_64:  "operator delete(void*)", referenced from:      _ijk_map_destroy in IJKMediaFramework(ijkstl.o)      std::__1::__tree<std::__1::__value_type<long long, void*>, std::__1::__map_value_compare<long long, std::__1::__value_type<long long, void*>, std::__1::less<long long>, true>, std::__1::allocator<std::__1::__value_type<long long, void*> > >::destroy(std::__1::__tree_node<std::__1::__value_type<long long, void*>, void*>*) in IJKMediaFramework(ijkstl.o)      std::__1::__tree<std::__1::__value_type<long long, void*>, std::__1::__map_value_compare<long long, std::__1::__value_type<long long, void*>, std::__1::less<long long>, true>, std::__1::allocator<std::__1::__value_type<long long, void*> > >::erase(std::__1::__tree_const_iterator<std::__1::__value_type<long long, void*>, std::__1::__tree_node<std::__1::__value_type<long long, void*>, void*>*, long>) in IJKMediaFramework(ijkstl.o)  "operator new(unsigned long)", referenced from:      _ijk_map_create in IJKMediaFramework(ijkstl.o)      std::__1::pair<std::__1::__tree_iterator<std::__1::__value_type<long long, void*>, std::__1::__tree_node<std::__1::__value_type<long long, void*>, void*>*, long>, bool> std::__1::__tree<std::__1::__value_type<long long, void*>, std::__1::__map_value_compare<long long, std::__1::__value_type<long long, void*>, std::__1::less<long long>, true>, std::__1::allocator<std::__1::__value_type<long long, void*> > >::__emplace_unique_key_args<long long, std::__1::piecewise_construct_t const&, std::__1::tuple<long long const&>, std::__1::tuple<> >(long long const&, std::__1::piecewise_construct_t const&&&, std::__1::tuple<long long const&>&&, std::__1::tuple<>&&) in IJKMediaFramework(ijkstl.o)ld: symbol(s) not found for architecture x86_64clang: error: linker command failed with exit code 1 (use -v to see invocation)

xcode 10 之后 需要添加  libc++.tbd