cgen doesn't create temporaries for arguments with multiple references

[zeozeozeo]

V doctor:

V full version: V 0.4.8 5c65e58.335bb63
OS: windows, Microsoft Windows 10 Pro v19045 64-bit
Processor: 10 cpus, 64bit, little endian, 

getwd: C:\Users\user\Downloads
vexe: C:\Users\user\Desktop\Code\v\v.exe
vexe mtime: 2024-11-03 09:59:01

vroot: OK, value: C:\Users\user\Desktop\Code\v
VMODULES: OK, value: C:\Users\user\.vmodules
VTMP: OK, value: C:\Users\user\AppData\Local\Temp\v_0

Git version: git version 2.42.0.windows.1
Git vroot status: weekly.2024.43-96-g335bb635
.git/config present: true

CC version: Error: 'cc' is not recognized as an internal or external command,

operable program or batch file.


thirdparty/tcc status: thirdparty-windows-amd64 b425ac82

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

fn takes_ref(x &&&&int) {
	unsafe { ****x = 5 }
}

fn main() {
	y := 4;
	takes_ref(y);
	println(y);
}

What did you expect to see?

5 in stdout

What did you see instead?

C:/Users/user/AppData/Local/Temp/v_0/test.01JBRWGXT25H4QKMQ8M9RWFQTW.tmp.c:7204: at print_backtrace_skipping_top_frames_tcc: Backtrace
C:/Users/user/AppData/Local/Temp/v_0/test.01JBRWGXT25H4QKMQ8M9RWFQTW.tmp.c:7171: by print_backtrace_skipping_top_frames
C:/Users/user/AppData/Local/Temp/v_0/test.01JBRWGXT25H4QKMQ8M9RWFQTW.tmp.c:8116: by unhandled_exception_handler
7ffd9d7c8b5c : by ???
C:/Users/user/AppData/Local/Temp/v_0/test.01JBRWGXT25H4QKMQ8M9RWFQTW.tmp.c:13738: at main__takes_ref: RUNTIME ERROR: invalid memory access
C:/Users/user/AppData/Local/Temp/v_0/test.01JBRWGXT25H4QKMQ8M9RWFQTW.tmp.c:13745: by main__main
C:/Users/user/AppData/Local/Temp/v_0/test.01JBRWGXT25H4QKMQ8M9RWFQTW.tmp.c:13784: by wmain
00467060 : by ???
004671c3 : by ???
7ffd9d447614 : by ???

Additional information
This equivalent program in Rust prints 5:

fn takes_ref(x: &mut &mut &mut &mut i32) {
    ****x = 5;
}

fn main() {
    let mut y = 4;
    takes_ref(&mut &mut &mut &mut y);
    println!("{y}");
}

The generated C code looks like this:

VV_LOCAL_SYMBOL void main__main(void) {
	int y = 4;;
	main__takes_ref((voidptr)&/*qq*/y);;
	println(int_str(y));;
}

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_{Huly®: V_0.6-21195}