https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97427
Bug ID: 97427
Summary: constexpr destructor for const object incorrectly
rejected as modifying const object
Product: gcc
Version: 11.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: ldalessandro at gmail dot com
Target Milestone: ---
The destructor below is rejected (see https://godbolt.org/z/M8YxTY). Workaround
for now is to mark n as mutable.
```
struct Foo {
int n = 1;
constexpr ~Foo() {
n = 0;
}
};
constexpr bool foo() {
const Foo b;
return true;
}
static_assert(foo());
```
The write to n is flagged as below.
```
<source>:13:18: error: non-constant condition for static assertion
13 | static_assert(foo());
| ~~~^~
<source>:13:18: in 'constexpr' expansion of 'foo()'
<source>:9:15: in 'constexpr' expansion of '((Foo*)(& b))->Foo::~Foo()'
<source>:4:11: error: modifying a const object '((Foo*)this)->Foo::n' is not
allowed in a constant expression
4 | n = 0;
```
