I've committed this patch to the devel/omp/gcc-12 branch. I will have to 
fold it into my previous OpenMP memory management patch series when I 
repost it.

The patch changes the internal memory allocation method such that memory 
is allocated in the regular heap and then marked as "coarse-grained", as 
opposed to allocating coarse-grained memory in the first place. The 
difference is that this is CPU first, not GPU first, which is typically 
the right way around, especially when we are using this for all possible 
allocations.

Andrew