I put these XMLs on C:\Program Files\CodeBlocks\share\CodeBlocks\compilers.
Our school used Turbo C++ 3.0 to teach programming and we switched to CodeBlocks + Borland Free C++ 5.5 compiler for a while. Now I want to upgrade to newer Borland Free C++ compiler to let the students use a more modern compiler and some new language standard features. Our curriculum was designed around that Borland C++ compiler and we used many specific features of it so switching to the GNU compiler caused our code to no longer compile. The plan is to switch to the GNU compiler in the future, but currently we still have to stick with Borland compiler.