Stack and heap in real mode

[Alexander Kuleshov]

Hello,

I'm reading source code of arch/x86/boot/header.S and
arch/x86/boot/main.c and can't understand is stack under heap in
memory or vice versa. I'm reading code and see that heap (if
CAN_USE_HEAP is set) is under the stack in memory but some comments in
code and documentation says that heap is above stack.

So am i right that stack is above heap?

Thank you.