Of those structures only vector benefits from realloc anyway. And if you really want it, it's not terribly hard to write. You can static assert that the template type is trivially movable which would make it safe to realloc.
But this is assuming you have a malloc implementation that does something other than implement realloc as just malloc+memcpy+free. Which not many do, not unless the allocation is so large as to be in its own dedicated mmap or similar.
That aside, sure would be great if you elaborated on these unsuitable, unresolved for kernel language issues? Exceptions and rtti are the only two I'm aware of and both have had off switches for decades.
But this is assuming you have a malloc implementation that does something other than implement realloc as just malloc+memcpy+free. Which not many do, not unless the allocation is so large as to be in its own dedicated mmap or similar.
That aside, sure would be great if you elaborated on these unsuitable, unresolved for kernel language issues? Exceptions and rtti are the only two I'm aware of and both have had off switches for decades.