Unexpected random values when appending aliased fixed array into array

[gechandesu]

V doctor:

V full version: V 0.4.8 5ec9bb5.fbc3fc6
OS: linux, Linux version 6.6.8-arch1-1 (linux@archlinux) (gcc (GCC) 13.2.1 20230801, GNU ld (GNU Binutils) 2.41.0) #1 SMP PREEMPT_DYNAMIC Thu, 21 Dec 2023 19:01:01 +0000
Processor: 16 cpus, 64bit, little endian, 12th Gen Intel(R) Core(TM) i5-1240P

getwd: /home/ge/Code/v/netaddr/fixed_array_issues
vexe: /home/ge/.vlang/v
vexe mtime: 2024-11-20 20:10:01

vroot: OK, value: /home/ge/.vlang
VMODULES: OK, value: /home/ge/.vmodules
VTMP: OK, value: /tmp/v_1000

Git version: git version 2.46.1
Git vroot status: weekly.2024.47-2-gfbc3fc6f
.git/config present: true

CC version: cc (GCC) 14.2.1 20240910
emcc version: N/A
thirdparty/tcc status: thirdparty-linux-amd64 0134e9b9

What did you do?
./v -g -o vdbg cmd/v && ./vdbg fixed_array_alias_append_to_array.v

module main

pub type Addr = [4]u8

fn main() {
	mut my_array := []Addr{}
	for i := 0; i <= 3; i++ {
		// After adding an element to the my_array array, we lose the value
		// of the right expression and as a result we get an array filled
		// with random data that changes every time the program is run.
		my_array << dump(Addr([u8(10), 0, 0, u8(i)]!))
	}
	assert my_array[0] == Addr([u8(10), 0, 0, 0]!)
	assert my_array[1] == Addr([u8(10), 0, 0, 1]!)
	assert my_array[2] == Addr([u8(10), 0, 0, 2]!)
	assert my_array[3] == Addr([u8(10), 0, 0, 3]!)
}

What did you expect to see?

Assertion passed.

What did you see instead?

[fixed_array_alias_append_to_array.v:17] Addr([u8(10), 0, 0, u8(i)]u8{}): Addr([10, 0, 0, 0])
[fixed_array_alias_append_to_array.v:17] Addr([u8(10), 0, 0, u8(i)]u8{}): Addr([10, 0, 0, 1])
[fixed_array_alias_append_to_array.v:17] Addr([u8(10), 0, 0, u8(i)]u8{}): Addr([10, 0, 0, 2])
[fixed_array_alias_append_to_array.v:17] Addr([u8(10), 0, 0, u8(i)]u8{}): Addr([10, 0, 0, 3])
fixed_array_alias_append_to_array.v:19: FAIL: fn main.main: assert my_array[0] == Addr([u8(10), 0, 0, 0]u8{})
  left value: my_array[0] = Addr([236, 0, 0, 0])
  right value: Addr([u8(10), 0, 0, 0]u8{})
V panic: Assertion failed...
v hash: fbc3fc6
/tmp/v_1000/fixed_array_alias_append_to_array.01JD5RC8QEHDGMD8T9ZF12HEQE.tmp.c:7476: at _v_panic: Backtrace
/tmp/v_1000/fixed_array_alias_append_to_array.01JD5RC8QEHDGMD8T9ZF12HEQE.tmp.c:14407: by main__main
/tmp/v_1000/fixed_array_alias_append_to_array.01JD5RC8QEHDGMD8T9ZF12HEQE.tmp.c:14499: by main

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_{Huly®: V_0.6-21368}