After a delay for more urgent matters, I have returned to using CodeBlocks and after some grappling with the .xml, I got a default.conf working OK with recent Clang and GNU GCC compilers.
I note that using Codeblocks always seems to make a lot of changes to the default.conf for reasons unclear to me.
I'd really like to remove all the unused (and not useful to me) compilers, leaving just the handful that I use, preferably at least at the top or bottom so that finding them is quicker.
But when I try remove unwanted compilers using CB, Settings, Compiler, chose Borland (say), the option for delete is grayed out.
If I use force majeur and delete the <bcc> ... </bcc> section, Codeblocks helpfull(?) restores it!
So this is hardcoded somewhere? Any suggestions on really removing unwanted compilers?