Home > Backend Development > C++ > Are C Struct Members Automatically Zero-Initialized?

Are C Struct Members Automatically Zero-Initialized?

DDD
Release: 2024-12-05 04:36:10
Original
180 people have browsed it

Are C   Struct Members Automatically Zero-Initialized?

Value Initialization of Struct Members in C

Consider the following struct:

struct Snapshot
{
    double x; 
    int y;
};
Copy after login

If the struct is declared without initialization, are its members automatically set to 0?

Answer:

No, members are not automatically initialized to 0. To set them to 0, explicit initialization is required:

Snapshot s = {0,0};
Copy after login

Other Initialization Options:

  • Value Initialization ({}): Initializes all members to their default values, e.g., 0 for numeric types.
Snapshot s = {}; // All members set to 0
Copy after login
  • Default Constructor: If the struct has a default constructor with member initialization, it will be used for implicit initialization.
struct Snapshot {
    int x = 0;
    double y = 0.0;
};

Snapshot s; // x = 0, y = 0.0
Copy after login
  • Constructor with Member Initialization: Custom initialization can be done using constructors.
struct Snapshot {
    Snapshot(int x, double y) : x(x), y(y) { }
};

Snapshot s(0, 0.0); // x = 0, y = 0.0
Copy after login

Note: Constructor initialization is not possible if there are aggregate initializer lists present in the struct declaration.

The above is the detailed content of Are C Struct Members Automatically Zero-Initialized?. For more information, please follow other related articles on the PHP Chinese website!

source:php.cn
Statement of this Website
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn
Popular Tutorials
More>
Latest Downloads
More>
Web Effects
Website Source Code
Website Materials
Front End Template