Can we have custom allocators in C?

[iboB]

Mixin allocators are allowed, but all others, the ones that are std::pmr::polymorphic_allocator in C++, are not. C code uses the default allocation for all of them.
Moreover since objects and mutations are fully wrapped to expose to C, every instance of an object or an allocation leads to new/delete.

The question is: can we solve one or both of these problems by allowing allocator customization from C?

[iboB]

The key is to port not the allocator, but memory resource