the error expression evaluated but not used is not reported for arr[i] or { break } inside a for loop

[zeozeozeo]

V doctor:

V full version: V 0.4.8 5c65e58.3108820
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: 2024-11-04 16:24:59

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.2024.45
.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 main() {
	arr := ["hello", "world"]
	for {
		arr[69] or { break }
	}
	println("0_o")
}

What did you expect to see?

error: expression evaluated but not used

What did you see instead?

================== C compilation error (from tcc): ==============
cc: C:/Users/user/AppData/Local/Temp/v_0/test.01JBW2ABZYYKVJ60MYXSQFBG1J.tmp.c:7156: warning: implicit declaration of function 'tcc_backtrace'
cc: C:/Users/user/AppData/Local/Temp/v_0/test.01JBW2ABZYYKVJ60MYXSQFBG1J.tmp.c:13762: error: ';' expected (got "}")
... (the original output was 3 lines long, and was truncated to 2 lines)
=================================================================
(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 .

Additional information
If another expression or statement is added after the faulty arr[69] or { break } line, the compiler correctly recognizes that the previous expression is unused, however doesn't report the newly inserted one:

fn main() {
	arr := ["hello", "world"]
	for {
		arr[69] or { break }
		1
	}
	println("0_o")
}

errors out with

test.v:4:11: error: expression evaluated but not used
    2 |     arr := ["hello", "world"]
    3 |     for {
    4 |         arr[69] or { break }
      |                 ~~~~~~~~~~~~
    5 |         1
    6 |     }

If expressions like arr[69] or { break } are not supposed to be reported as unused, this should probably be considered a cgen error, as the generated C code does not compile.

This will print 0_o, but should be an error:

fn main() {
    arr := ["hello", "world"]
    for {
        arr[69] or { break }.len
    }
    println("0_o")
}

_{Huly®: V_0.6-21207}

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