https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115603
Bug ID: 115603
Summary: [concepts] differing declaration and definition do not
give error
Product: gcc
Version: 14.1.1
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: ispavlick at gmail dot com
Target Milestone: ---
#include <vector>
#include <functional>
#include <iostream>
template <typename T>
requires std::is_pointer_v<T>
using stored_not_null = T;
template <int column_cnt>
class Table;
template <int column_cnt>
class Data_with_refresh
{
Table<column_cnt> *m_table;
public:
// Declaration does not match with defenition.
// stored_not_null<Table<column_cnt>> violates constraint,
// defeition - does not
Data_with_refresh(stored_not_null<Table<column_cnt>> *table);
void fn();
};
template <int column_cnt>
using enter_cb = std::function<void(Data_with_refresh<column_cnt> d)>;
template <int column_cnt>
class Table
{
enter_cb<column_cnt> m_entercb;
public:
Table(enter_cb<column_cnt> entercb) {
m_entercb = std::move(entercb);
m_entercb(this);
}
void refresh() {std::cout << "tick" << std::endl;}
};
// Defenition is different, and does not violates contstraint
template <int column_cnt>
Data_with_refresh<column_cnt>::Data_with_refresh(
stored_not_null<Table<column_cnt> *> table)
: m_table(table) {}
template <int column_cnt>
void Data_with_refresh<column_cnt>::fn()
{
m_table->refresh();
}
int main()
{
Table<3> tt([](Data_with_refresh<3> dd) {
dd.fn();
});
}
gcc compiles this without errors and warnings, clang gives compile time error
