cpp/src/CMakeLists.txt was altered for mingw builds in
The qpidxarm target builds the XA distributed transaction resource manager for use with the Microsoft distributed trasanction coordinator. It was targeted for Windows builds only, using the CMake variable "WIN32".
This variable was changed to "_MSC_VER" for
QPID-2905, presumably to indicate that the build target should only apply to builds using the Microsoft compiler, and not mingw. Unfortunately "_MSC_VER" is not a recognized CMAKE variable and the qpidxarm target is never generated.
The CMake documentation indicates the the variable "MSVC" should be used to indicate The Microsoft compiler compared to mingw.