stackminne

Stackminne, or stack memory, is the region of a program’s address space used to store activation records for function calls. Each time a function is invoked, a new stack frame is created containing the return address, saved registers, function parameters, and local automatic variables. Frames are pushed onto the stack on entry and popped on return, following a last-in, first-out (LIFO) discipline.

In most systems the stack is per thread and grows in a direction determined by the architecture; many commonly used architectures have stacks that grow downward toward lower memory addresses, while others grow upward. The stack is typically very fast to access and is managed automatically by the compiler and runtime, with a prologue saving state and an epilogue restoring it.

Stack size is finite and can be exhausted. Large or deeply nested local allocations, heavy use of recursion, or large variadic parameter handling can lead to stack overflow. Operating systems may implement guard pages or other protections to detect overflow, and some languages or runtimes use techniques such as stack canaries or shadow stacks to improve security against certain exploits.

Contents of a stack frame commonly include the return address, saved callee-saved registers, function parameters that were passed on the stack, and space for local variables and temporaries. In languages with managed runtimes, the stack may also hold frames for the language runtime, while large data is typically allocated on the heap. Stack usage is a key factor in performance and reliability, influencing recursion limits and memory safety strategies.