[Issue 20546] Сast nested array from static to dynamic.

[d-bugmail at puremagic.com]

https://issues.dlang.org/show_bug.cgi?id=20546

moonlightsentinel at disroot.org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
                 CC|                            |moonlightsentinel at disroot.o
                   |                            |rg
         Resolution|---                         |INVALID

--- Comment #1 from moonlightsentinel at disroot.org ---
The cast from int[2][2] to int[][] is invalid - you cannot slice across
multiple dimensions.

import std.stdio;

void main(string[] args)
{
    int[2][2] e = [[1,2],[3,4]];
    int[][] c = cast(int[][]) e;

    writeln(c.length);    // 1
    writeln(c[0].length); // 8589934593

    int[2][] valid = e; // no cast needed
    writeln(valid);     // [[1, 2], [3, 4]]
}

The length of a static array is only known at compile time while the length of
a dynamic array is a runtime value. Hence c's length is set to some garbage
from the stack.

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