读取未初始化的变量
Reading uninitialized variable
读取未初始化的变量会导致未定义的行为，例如
#include <iostream>
int main()
{
int a;
std::cout << a << std::endl; // undefined behavior
}
有人可以对这个事实给出正式的解释吗？
这里是相关的部分，我认为：
4.1 Lvalue-to-rvalue conversion
1 - A glvalue of a non-function, non-array type T can be converted to a prvalue. If T is an incomplete
type, a program that necessitates this conversion is ill-formed. If
the object to which the glvalue refers is not an object of type T and
is not an object of a type derived from T, or if the object is
uninitialized, a program that necessitates this conversion has
undefined behavior.
变量是左值，我认为“左值到右值的转换”是获取变量值的过程。
(注意 - 我不熟悉 C++ 标准，所以我可能没有找到适用于此示例的部分。我所做的只是在 PDF 中搜索“未初始化”，然后查找匹配项看起来最相关。）
读取未初始化的变量会导致未定义的行为，例如
#include <iostream>
int main()
{
int a;
std::cout << a << std::endl; // undefined behavior
}
有人可以对这个事实给出正式的解释吗？
这里是相关的部分，我认为：
4.1 Lvalue-to-rvalue conversion
1 - A glvalue of a non-function, non-array type T can be converted to a prvalue. If T is an incomplete type, a program that necessitates this conversion is ill-formed. If the object to which the glvalue refers is not an object of type T and is not an object of a type derived from T, or if the object is uninitialized, a program that necessitates this conversion has undefined behavior.
变量是左值，我认为“左值到右值的转换”是获取变量值的过程。
(注意 - 我不熟悉 C++ 标准，所以我可能没有找到适用于此示例的部分。我所做的只是在 PDF 中搜索“未初始化”，然后查找匹配项看起来最相关。）