https://gcc.gnu.org/bugzilla/show_bug.cgi?id=124057
Bug ID: 124057
Summary: GCC still rejects C++26 contexpr std::span using
std::initializer_list
Product: gcc
Version: 16.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: jlame646 at gmail dot com
Target Milestone: ---
The following program should be accepted by gcc using P2447 but gcc trunk still
rejects it:
```
#include <span>
#include<initializer_list>
int main(int argc, char **argv) {
constexpr std::span<const int> s = {0,0};//should be accepted as of c++26
p2447
}
```
But gcc incorrectly rejects it:
```
<source>: In function 'int main(int, char**)':
<source>:4:45: error: 'std::span<const int>{((const int*)(&<anonymous>)),
std::__detail::__extent_storage<18446744073709551615>{2}}' is not a constant
expression
4 | constexpr std::span<const int> s = {0,0};//should be accepted as
of c++26 p2447
| ^
<source>:4:45: error: 'std::span<const int>(std::initializer_list<int>{((const
int*)(& const int [2]{0, 0})), 2})' is not a constant expression because it
refers to an incompletely initialized variable
Compiler returned: 1
```
Note that other compiler also rejects it.
