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Copy pathnop.cpp
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55 lines (53 loc) · 1.6 KB
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/**
* Certified Null Operation in C++
*
* A program that does absolutely nothing at the application level.
* Returns 0 (success) without any side effects.
*
* CNO Properties Demonstrated:
* - Termination: Returns immediately from main
* - Purity: No side effects, no I/O, no mutation
* - State Preservation: System state unchanged (at logical level)
* - Determinism: Always produces same (null) result
*
* Compilation:
* g++ -std=c++17 -O2 nop.cpp -o nop
* clang++ -std=c++17 -O2 nop.cpp -o nop
*
* Execution:
* ./nop
* echo $? # Should output 0
*/
int main() {
return 0;
}
/*
* Verification Notes:
* ==================
*
* Logical Level:
* - This is a pure CNO: no observable effects
* - main() receives argc/argv but doesn't access them
* - No heap allocation, no stack manipulation (beyond frame setup)
* - No exception handling needed
*
* Physical Level:
* - C++ runtime initialization occurs (global constructors)
* - Stack frame allocated and deallocated
* - Return value passed through registers (typically RAX on x86-64)
* - CPU cycles consumed
*
* Assembly Analysis:
* With -O2 optimization, this typically compiles to:
* xor eax, eax ; Set return value to 0
* ret ; Return
*
* Contrast with C:
* - C++ requires name mangling consideration (not relevant here)
* - C++ runtime is heavier (global constructor/destructor support)
* - But at application level: identical CNO behavior
*
* Philosophy:
* This demonstrates the platonic ideal of "doing nothing" in C++.
* Even though the C++ runtime does work, the user code is perfectly inert.
*/