xref: /llvm-project/clang/test/Analysis/issue-94193.cpp (revision 566363981bb9ff6a6081490f05aa6b19aefc16f0)
1 // RUN: %clang_analyze_cc1 %s -verify -analyzer-checker=core
2 
3 #include "Inputs/system-header-simulator-cxx.h"
4 
5 
6 namespace GH94193 {
7 template<typename T> class optional {
8   union {
9     char x;
10     T uvalue;
11   };
12   bool holds_value = false;
13 public:
14   optional() = default;
15   optional(const optional&) = delete;
16   optional(optional&&) = delete;
17   template <typename U = T> explicit optional(U&& value) : holds_value(true) {
18     new (static_cast<void*>(std::addressof(uvalue))) T(std::forward<U>(value));
19   }
20   optional& operator=(const optional&) = delete;
21   optional& operator=(optional&&) = delete;
22   explicit operator bool() const {
23     return holds_value;
24   }
25   T& unwrap() & {
26     return uvalue; // no-warning: returns a valid value
27   }
28 };
29 
30 int top1(int x) {
31   optional<int> opt{x}; // note: Ctor was inlined.
32   return opt.unwrap();  // no-warning: returns a valid value
33 }
34 
35 std::string *top2() {
36   std::string a = "123";
37   // expected-warning@+2 {{address of stack memory associated with local variable 'a' returned}} diagnosed by -Wreturn-stack-address
38   // expected-warning@+1 {{Address of stack memory associated with local variable 'a' returned to caller [core.StackAddressEscape]}}
39   return std::addressof(a);
40 }
41 } // namespace GH94193
42