https://gcc.gnu.org/bugzilla/show_bug.cgi?id=119688
Bug ID: 119688
Summary: literal operator template instantiated only once
(c++20)
Product: gcc
Version: 14.2.1
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: yannick.daveluy at gmail dot com
Target Milestone: ---
With user defined literal operator template there is a problem of template
instantiation. It seems the the first instantiation stay in cache.
Here is a reproducible program:
```c++
#include <array>
template <std::size_t N> struct builder {
std::array<bool, 256> value{};
explicit(false) constexpr builder(char const (&s)[N]) {
for(auto i = 0 ; i < N;++i)
value[static_cast<unsigned char>(s[i])] = true;
}
};
template<builder A>
constexpr auto operator""_ar() {
return A.value;
}
constexpr auto first = "ab"_ar;
static_assert(first['a']);
static_assert(first['b']);
static_assert(!first['c']);
static_assert(!first['d']);
constexpr auto second = "cd"_ar;
static_assert(!second['a']); // error: static assertion failed
static_assert(!second['b']); // error: static assertion failed
static_assert(second['c']); // error: static assertion failed
static_assert(second['d']); // error: static assertion failed
// -> second seems to be equal to "ab"_cr instead of ""cd"_cr
```
FYI this code works as expected using Clang.
