`pub` field of private struct is accessible outside the module

[gechandesu]

Describe the bug

The subject.

Reproduction Steps

// foo.v
module foo

struct Foo {
pub:
        bar int
}

pub fn new(bar int) Foo {
        return Foo{bar}
}

// main.v
module main

import foo

fn main() {
        f := foo.new(12)
        println(f)
        println(f.bar)
}

Expected Behavior

Compilation error. Since the Foo struct is not public, its fields must not be public either.

Current Behavior

Output:

foo.Foo{
    bar: 12
}
12 // access to Foo.bar field

Possible Solution

No response

Additional Information/Context

No response

V version

V 0.5.0 4b19e9e

Environment details (OS name and version, etc.)

V full version	V 0.5.0 19e79c4.4b19e9e
OS	linux, Linux version 6.18.7-arch1-1 (linux@archlinux) (gcc (GCC) 15.2.1 20260103, GNU ld (GNU Binutils) 2.45.1) #1 SMP PREEMPT_DYNAMIC Sat, 24 Jan 2026 00:47:39 +0000
Processor	16 cpus, 64bit, little endian, 12th Gen Intel(R) Core(TM) i5-1240P
Memory	1GB/15.34GB
V executable	/home/ge/.vlang/v
V last modified time	2026-02-18 09:32:04
V home dir	OK, value: /home/ge/.vlang
VMODULES	OK, value: /home/ge/.vmodules
VTMP	OK, value: /tmp/v_1000
Current working dir	OK, value: /tmp/pubfield
Git version	git version 2.53.0
V git status	weekly.2026.03-320-g4b19e9e4
.git/config present	true
cc version	cc (GCC) 15.2.1 20260103
gcc version	gcc (GCC) 15.2.1 20260103
clang version	clang version 21.1.6
tcc version	tcc version 0.9.28rc 2025-02-13 HEAD@f8bd136d (x86_64 Linux)
tcc git status	thirdparty-linux-amd64 696c1d84
emcc version	N/A
glibc version	ldd (GNU libc) 2.42

Note

You can use the 👍 reaction to increase the issue's priority for developers.

Please note that only the 👍 reaction to the issue itself counts as a vote.
Other reactions and those to comments will not be taken into account.

[jorgeluismireles]

Is interesting your position, now I have doubts. Since it should mean a private struct with at least one public member or method, like this:

struct Foo {
pub:
        bar int
}

should have marked with a "warning" since does not matter field bar is public should never be visible outside because struct it isn't. And should be mandatory to declare as public the struct having at least a single public field or method:

pub struct Foo {
pub:
        bar int
}

Thoughs?

[blackshirt]

By definition

pub fn new(bar int) Foo {
        return Foo{bar}
}

Its make Foo was avaialbles outside the modules .. and i think its the right semantic availables when created with constructor, and not availables outside the world directly. Its also mean, the public fields or methods becomes availables too.

See similar construct from crypto.sha256, sha512 ..etc in the form of Digest opaque. The Digest itself was not pub-licly availables directly, and only availables through new constructor. but the public methods was availables to outside.

I think there are many similar construct like them on the standard library.