What this C++ code-output question tests
This is a hard C++ question that probes your understanding of language semantics and object identity in ways that often surprise even experienced programmers. It rewards precise knowledge of how the compiler and runtime handle specific constructs, rather than guesswork or pattern-matching.
To answer correctly, you need to trace through the code mentally and understand the exact behaviour of the relevant C++ features at play. The question tests whether you can reason about what actually executes versus what you might intuitively expect, and whether you know the subtle rules that govern the output.
- Object construction and identity
- Compiler-level code generation
- Language-specific semantics and edge cases
- Distinguishing what code does from what you assume it does