Introduction / Context:
A function prototype communicates a function's name, return type, and parameter types to the compiler before the function is used. This is critical for type checking, overload resolution (C++), and correct code generation. The question asks at which stage we provide that prototype in normal C/C++ development flow.
Given Data / Assumptions:
- A function's signature must be known to the compiler before it is called.
- Prototypes are typically placed in header files that are included where needed.
- We distinguish between declaration (prototype) and definition (body).
Concept / Approach:
- A declaration introduces an identifier and its type; for functions, that is the prototype.
- A definition provides the actual function body.
- Calling is the act of invoking a function; it requires that a declaration is already visible.
Step-by-Step Solution:
Identify what a prototype contains: return type + name + parameter types.Recognize that providing this information is exactly a function declaration, not a definition.Therefore, the stage is Declaring.
Verification / Alternative check:
Example: 'int sum(int a, int b);' (declaration/prototype) can appear in a header; the body appears in a source file.
Why Other Options Are Wrong:
- Defining: Includes the body; the prototype exists even without the body.
- Prototyping: Not a standard stage name; the correct term is 'declaring'.
- Calling: Requires that the prototype (declaration) already be known.
Common Pitfalls:
- Confusing the term 'prototype' with the implementation; only the signature is needed to call.
- Omitting prototypes leads to implicit declarations (illegal in modern C) or compiler errors.
Final Answer:
Declaring
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