https://gcc.gnu.org/bugzilla/show_bug.cgi?id=119097
Bug ID: 119097
Summary: Modules references internal linkage entity
Product: gcc
Version: 14.2.1
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: hypengwip at gmail dot com
Target Milestone: ---
When a variable is declared inside an unnamed namespace in a header file and
then used in a struct definition, it causes a compilation error due to internal
linkage. The issue occurs when the struct is used both in a header (.h) and
inside a module (.cppm).
However, using the same variable in a function inside a module (.cppm) does not
produce any error.
```
// error: ‘struct A’ references internal linkage entity 'constexpr const int
{anonymous}::default_val'`
// part1.h
#pragma once
namespace {
static constexpr const int default_val { 0 };
}
// if define A here
struct A {
int value { default_val }; // failed
A() : value(default_val) {} // failed
static auto a() { return default_val; } // failed
};
// part1.cppm
module;
#include "part1.h"
export module mymod;
// if define A here
struct A {
int value { default_val }; // failed
A() : value(default_val) {} // ok
static auto a() { return default_val; } // ok
};
export auto a() { return default_val; } // ok
export void part1_fun(A) {}
```
