https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113791
Bug ID: 113791
Summary: Incorrect handling of lvalue to rvalue conversion in
ternary operator
Product: gcc
Version: 13.2.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: Mark_B53 at yahoo dot com
Target Milestone: ---
#include <unordered_map>
#include <iostream>
template<template<class, class, class...> class Map, typename Key, typename T,
typename KeyP, typename... Args>
T getMapEntry(const Map<Key, T, Args...>& map, const KeyP& key, T&& defval) {
static_assert(std::is_convertible_v<KeyP, Key>);
auto i = map.find(key);
return i != map.end() ? i->second : std::move(defval);
}
class Foo {
public:
Foo() { std::cout << __PRETTY_FUNCTION__ << '\n'; }
~Foo() { std::cout << __PRETTY_FUNCTION__ << '\n'; }
Foo(const Foo&) { std::cout << __PRETTY_FUNCTION__ << '\n'; }
Foo& operator=(const Foo&) { std::cout << __PRETTY_FUNCTION__ << '\n';
return *this; }
Foo(Foo&&) { std::cout << __PRETTY_FUNCTION__ << '\n'; }
Foo& operator=(Foo&&) { std::cout << __PRETTY_FUNCTION__ << '\n'; return
*this; }
};
int main() {
std::unordered_map<int, Foo> map;
auto&& ret = getMapEntry(map, 123U, Foo{});
return 0;
}
GCC outputs:
Foo::Foo()
Foo::Foo(Foo&&)
Foo::~Foo()
Foo::~Foo()
Correct output:
Foo::Foo()
Foo::Foo(const Foo &)
Foo::~Foo()
Foo::~Foo()
Posted on https://stackoverflow.com/questions/77948860/
Maybe related to https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87605
