Incorrect `void[]` casts are generated in cgen

[XiaoPangxie732]

Describe the bug

void[] casts are incorrectly generated in cgen

Reproduction Steps

fn main() {
    v := match 12 {
        12 {
            x := if true { 'b' } else { some_func()? }
            println(x)
            x
        }
        else { none }
    }
    println(v)
}

fn some_func() ?string {
    return 'a'
}

Expected Behavior

b

Current Behavior

================== C compilation error (from tcc): ==============
cc: C:/Users/***/AppData/Local/Temp/v_0/test.01JQ7ADWEF0G0N8ZR7H1CDQS5S.tmp.c:3786: warning: implicit declaration of function 'tcc_backtrace'
cc: C:/Users/***/AppData/Local/Temp/v_0/test.01JQ7ADWEF0G0N8ZR7H1CDQS5S.tmp.c:5806: error: declaration of an array of incomplete type elements
...
cc: C:/Users/***/AppData/Local/Temp/v_0/test.01JQ7ADWEF0G0N8ZR7H1CDQS5S.tmp.c:5806: error: declaration of an array of incomplete type elements
(note: the original output was 3 lines long; it was truncated to its first 2 lines + the last line)
=================================================================
(You can pass `-cg`, or `-show-c-output` as well, to print all the C error messages).
builder error:
==================
C error found. It should never happen, when compiling pure V code.
This is a V compiler bug, please report it using `v bug file.v`,
or goto https://github.com/vlang/v/issues/new/choose .
You can also use #help on Discord: https://discord.gg/vlang .

Possible Solution

No response

Additional Information/Context

This C code is generated:

_option_string _t1 = (_option_string){.state=2, .err=_const_none__, .data={EMPTY_STRUCT_INITIALIZATION}};
    
if (12 == (12)) {
    string _t2; /* if prepend */
    if (true) {
        _option_ok(&(string[]) { _SLIT("b") }, (_option*)(&_t2), sizeof(string));
    } else {
        _option_string _t3 = main__some_func();
        if (_t3.state != 0) {
            panic_option_not_set( IError_name_table[_t3.err._typ]._method_msg(_t3.err._object) );
        }
        
         _option_ok(&(string[]) { (*(string*)_t3.data) }, (_option*)(&_t2), sizeof(string));
    }
    string x = _t2;
    println(x);
    _option_ok(&(void[]) { x }, (_option*)(&_t1), sizeof(void));
}
else {
    _t1.state = 2;
    _t1.err = _const_none__;
}_option_string v = _t1;
println(_option_string_str(v));

There is a void[] cast, which is meaningless
Also, this example triggers #24047

V version

V 0.4.10 e968139

Environment details (OS name and version, etc.)

V full version	V 0.4.10 725e259.e968139
OS	windows, Microsoft Windows 11 Pro 26100 64-bit
Processor	12 cpus, 64bit, little endian, Intel(R) Core(TM) i7-8700K CPU @ 3.70GHz
Memory	2.44GB/15.86GB
V executable	E:\Programs\v\v.exe
V last modified time	2025-03-25 18:45:38
V home dir	OK, value: E:\Programs\v
VMODULES	OK, value: C:\Users***.vmodules
VTMP	OK, value: C:\Users***\AppData\Local\Temp\v_0
Current working dir	OK, value: ***
Git version	git version 2.38.1.windows.1
V git status	0.4.10-39-ge9681394
.git/config present	true
cc version	N/A
gcc version	N/A
clang version	N/A
msvc version	N/A
tcc version	tcc version 0.9.27 (x86_64 Windows)
tcc git status	thirdparty-windows-amd64 b425ac82
emcc version	N/A
glibc version	N/A

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