https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114913
--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
here is a C++11 testcase:
```
struct strt {
char *_M_dataplus;
char _M_local_buf=0;
constexpr strt()
: _M_dataplus(&_M_local_buf) {}
constexpr strt(const strt &__str)
: _M_dataplus(&_M_local_buf) {}
};
constexpr strt
f() {
return {};
}
constexpr strt HelloWorld = f();
const char *a() { return HelloWorld._M_dataplus; }
```
it was rejected before GCC 10 with the following error message:
```
<source>:13:31: error: 'strt{(&<anonymous>.strt::_M_local_buf), '\000'}' is not
a constant expression
13 | constexpr strt HelloWorld = f();
| ^
```
Maybe that will give an hint where the issue is ...
