| ***NOTE*** | |
| If you get linker errors about undefined references to symbols that involve types in the `std::__cxx11` namespace or the tag | |
| `[abi:cxx11]` then it probably indicates that you are trying to link together object files that were compiled with different | |
| values for the _GLIBCXX_USE_CXX11_ABI marco. This commonly happens when linking to a third-party library that was compiled with | |
| an older version of GCC. If the third-party library cannot be rebuilt with the new ABI, then you need to recompile your code with | |
| the old ABI,just like: | |
| **g++ stringWrite.cpp -ljsoncpp -std=c++11 -D_GLIBCXX_USE_CXX11_ABI=0 -o stringWrite** | |
| Not all of uses of the new ABI will cause changes in symbol names, for example a class with a `std::string` member variable will | |
| have the same mangled name whether compiled with the older or new ABI. In order to detect such problems, the new types and functions | |
| are annotated with the abi_tag attribute, allowing the compiler to warn about potential ABI incompatibilities in code using them. | |
| Those warnings can be enabled with the `-Wabi-tag` option. |