https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101781
Bug ID: 101781
Summary: make_unique generating a warning with -fanalyzer
Product: gcc
Version: 11.2.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: deco33000 at yandex dot com
Target Milestone: ---
Hi,
given the following code
// Type your code here, or load an example.
#include <iostream>
#include <vector>
#include <memory>
using namespace std;
int main() {
auto res = make_unique<int>();
auto ptr = res.get();
if (ptr) {
*ptr = 5;
cout << *ptr << endl;
}
return 0;
}
I get warning: dereference of possibly-NULL 'operator new(4)' [CWE-690]
[-Wanalyzer-possible-null-dereference]
Whereas I check sufficiently not to dereference that pointer if not set.
Apparently, the compiler doesn't like that make_unique doesn't check the return
of new. Even then, the code avoiding make_unique:
int main() {
auto i = new int(0);
if (!i) {
return 1;
}
unique_ptr<int> res(i);
auto ptr = res.get();
if (!ptr) {
return 1;
}
*ptr = 5;
cout << *ptr << endl;
return 0;
}
Still gives the same warning.
try on Godbolt:
https://godbolt.org/z/8399T1511
and
https://godbolt.org/z/5jjM4E5Ec
Thanks
