c - C如何分配多维数组中的数据项？

Question

我想了解 C 将如何分配多维数组的数据项，以及它们的分配在机器之间是否一致。

我知道，在最低层，数据项是相邻的，但我不知道它们在更上层是如何排列的。

例如，如果我将一个 3D 数组分配为 int threeD[10][5][6]，我可以假设 &(threeD[4][2][5 ]) + 1 == &(threeD[4][3][0])?在所有机器上？

预先感谢您的帮助。

Answer 1

是的，数组在 C 编译器的所有实现中都按行主顺序存储。
标准说(我应用了一些重新格式化):

6.5.2.1 Array subscripting
    Constraints

3   Successive subscript operators designate an element of a multidimensional
    array object.  
    If E is an n-dimensional array (n >= 2) with dimensions i * j * . . . * k,
    then E (used a s other than an lvalue) is converted to a pointer to an
    (n - 1)-dimensional array with dimensions j * . . . * k.
    If the unary * operator is applied to this pointer explicitly, or
    implicitly as a result of subscripting, the result is the pointed-to
    (n - 1)-dimensional array, which itself is converted into a pointer if
    used as other than an lvalue. It follows from this that arrays are stored
    in row-major order (last subscript varies fastest).