如果我有一个带有数组成员的结构,并且我在结构的构造函数中显式调用了数组的默认构造函数,那么元素是否会默认构造？ (在整数数组的情况下,这将意味着零初始化).
struct S
{
S() : array() {}
int array[SIZE];
};
...
S s;
// is s.array zero-initialized?
使用gcc进行的快速测试表明情况确实如此,但我想确认我可以依赖这种行为.
解决方法
是的(突出我的)：
(C++03 8.5)
To value-initialize an object of type T means:
if T is a class type (clause 9) with a user-declared constructor (12.1),then the default constructor for T is called (and the initialization is ill-formed if T has no accessible default constructor);
if T is a non-union class type without a user-declared constructor,then every non-static > data member and baseclass component of T is value-initialized
if T is an array type,then each element is value-initialized;
otherwise,the object is zero-initialized
…
An object whose initializer is an empty set of parentheses,i.e.,(),shall be value-initialized.
