如何在结构数组中初始化数组？

Question

Let's assume I have a structure defined as:

typedef struct _TStruct {

    uint Values[3];

} TStruct;

Then I define an array of structures:

TStruct Data[3];

How do I correctly initialize the arrays in this array of structures?

Answer 1

To correctly initialize an array in an array of structures you need to do the following:

typedef struct _TStruct {

    uint Values[3];

} TStruct;

TStruct Data[3] = {

    {{ 0x86, 0x55, 0x79 }}, {{ 0xaa, 0xbb, 0xcc }}, {{ 0x76, 0x23, 0x24 }}

}; 

Pay attention to the double braces around every group of values. The additional pair of braces is essential to avoid getting a following gcc error (only when -Wall flag is present, precisely it's "detected" by gcc -Wmissing-braces flag):

warning: missing braces around initializer

Note :

1. Usage of double braces {{ }} does not change the layout of data in memory

2. This warning does not appear on MS Visual Studio C++ compiler

See also:

How to repair warning: missing braces around initializer?

GCC Bug 53319