1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
|
// RUN: %clang_analyze_cc1 %s -verify -analyzer-checker=core
#include "Inputs/system-header-simulator-cxx.h"
namespace GH94193 {
template<typename T> class optional {
union {
char x;
T uvalue;
};
bool holds_value = false;
public:
optional() = default;
optional(const optional&) = delete;
optional(optional&&) = delete;
template <typename U = T> explicit optional(U&& value) : holds_value(true) {
new (static_cast<void*>(std::addressof(uvalue))) T(std::forward<U>(value));
}
optional& operator=(const optional&) = delete;
optional& operator=(optional&&) = delete;
explicit operator bool() const {
return holds_value;
}
T& unwrap() & {
return uvalue; // no-warning: returns a valid value
}
};
int top1(int x) {
optional<int> opt{x}; // note: Ctor was inlined.
return opt.unwrap(); // no-warning: returns a valid value
}
std::string *top2() {
std::string a = "123";
// expected-warning@+2 {{address of stack memory associated with local variable 'a' returned}} diagnosed by -Wreturn-stack-address
// expected-warning@+1 {{Address of stack memory associated with local variable 'a' returned to caller [core.StackAddressEscape]}}
return std::addressof(a);
}
} // namespace GH94193
|
