@intFromPtr not forwarding undefined poison value for UB detection

[nektro]

Zig Version

0.12.0-dev.1828+225fe6ddb

Steps to Reproduce and Observed Behavior

test {
    const val: []const u8 = "sdfkjdkvlsvj";
    const slice: []u32 = undefined;
    var x: u16 = 0;
    if (@intFromPtr(val.ptr) != @intFromPtr(slice.ptr)) {
        x += 1;
    }
}

❯ zig test test.zig 
All 1 tests passed.

Expected Behavior

either compile error or runtime error tripping a safety check

[Vexu]

Hits unreachable with a debug build:

/home/vexu/Documents/zig/zig/src/value.zig:535:27: 0xa19843f in getUnsignedIntAdvanced (zig)
                .undef => unreachable,
                          ^
/home/vexu/Documents/zig/zig/src/Sema.zig:9890:56: 0xa880152 in zirIntFromPtr (zig)
                (try operand_val.getUnsignedIntAdvanced(mod, sema)).?,
                                                       ^
/home/vexu/Documents/zig/zig/src/Sema.zig:1123:68: 0xa454660 in analyzeBodyInner (zig)
            .int_from_ptr                 => try sema.zirIntFromPtr(block, inst),
                                                                   ^

[xdBronch]

this was fixed in #19630

$ Downloads/zig-linux-x86_64-0.12.1/zig test a.zig
a.zig:5:33: error: use of undefined value here causes undefined behavior
    if (@intFromPtr(val.ptr) != @intFromPtr(slice.ptr)) {
                                ^~~~~~~~~~~~~~~~~~~~~~