如果不将缓冲区声明为C中的全局变量，为什么会发生堆栈溢出？

Question

Just read somewhere that,

when large buffers are used they must be made global variables otherwise stack overflow occurs.

But i am unable to get why it would happen?

(This is for C language compilers Turbo C on windows).

Answer 1

全局变量不在堆栈上分配-它们位于可执行文件的读写部分，因此不会导致堆栈溢出。

Answer 2

Typically, the executable file header, and OS loader, place a lower limit on the maximum stack size than they do on the global/static data.

Your linker is responsible for assembling the executable header and may be instructed to set a greater, (or smaller), maximum stack size for the executable image, so you could instruct the linker to raise that limit to accommodate your big buffer.

If you need a large buffer and don't want to increase the maximum stack, you could dynamically-allocate the buffer space at runtime.

The last option you should consider is using statics/globals. Such code/data is not reeentrant and so not thread-safe:(