xref: /llvm-project/clang/test/Analysis/trivial-copy-struct.cpp (revision 6194229c6287fa5d8a9a30aa489bcbb8a9754ae0)
1 // RUN: %clang_analyze_cc1 -analyzer-checker=core,debug.ExprInspection -verify %s
2 
3 template <typename T> void clang_analyzer_dump(T);
4 template <typename T> void clang_analyzer_value(T);
5 void clang_analyzer_warnIfReached();
6 
7 struct Node { int* ptr; };
8 
copy_on_stack(Node * n1)9 void copy_on_stack(Node* n1) {
10   Node tmp = *n1;
11   Node* n2 = &tmp;
12   clang_analyzer_dump(n1); // expected-warning-re {{&SymRegion{reg_${{[0-9]+}}<Node * n1>}}}
13   clang_analyzer_dump(n2); // expected-warning {{&tmp}}
14 
15   clang_analyzer_dump(n1->ptr); // expected-warning-re {{&SymRegion{reg_${{[0-9]+}}<int * Element{SymRegion{reg_${{[0-9]+}}<Node * n1>},0 S64b,struct Node}.ptr>}}}
16   clang_analyzer_dump(n2->ptr); // expected-warning-re {{&SymRegion{reg_${{[0-9]+}}<int * Element{SymRegion{reg_${{[0-9]+}}<Node * n1>},0 S64b,struct Node}.ptr>}}}
17 
18   if (n1->ptr != n2->ptr)
19     clang_analyzer_warnIfReached(); // unreachable
20   (void)(n1->ptr);
21   (void)(n2->ptr);
22 }
23 
copy_on_heap(Node * n1)24 void copy_on_heap(Node* n1) {
25   Node* n2 = new Node(*n1);
26 
27   clang_analyzer_dump(n1); // expected-warning-re {{&SymRegion{reg_${{[0-9]+}}<Node * n1>}}}
28   clang_analyzer_dump(n2); // expected-warning-re {{&HeapSymRegion{conj_${{[0-9]+}}{Node *, LC{{[0-9]+}}, S{{[0-9]+}}, #{{[0-9]+}}}}}}
29 
30   clang_analyzer_dump(n1->ptr); // expected-warning-re {{&SymRegion{reg_${{[0-9]+}}<int * Element{SymRegion{reg_${{[0-9]+}}<Node * n1>},0 S64b,struct Node}.ptr>}}}
31   clang_analyzer_dump(n2->ptr); // expected-warning-re {{&SymRegion{reg_${{[0-9]+}}<int * Element{SymRegion{reg_${{[0-9]+}}<Node * n1>},0 S64b,struct Node}.ptr>}}}
32 
33   if (n1->ptr != n2->ptr)
34     clang_analyzer_warnIfReached(); // unreachable
35   (void)(n1->ptr);
36   (void)(n2->ptr);
37 }
38 
39 struct List {
40   List* next;
41   int value;
42   int padding;
43 };
44 
deadCode(List orig)45 void deadCode(List orig) {
46   List c = orig;
47   clang_analyzer_dump(c.value);
48   // expected-warning-re@-1 {{reg_${{[0-9]+}}<int orig.value>}}
49   if (c.value == 42)
50     return;
51   clang_analyzer_value(c.value);
52   // expected-warning@-1 {{32s:{ [-2147483648, 41], [43, 2147483647] }}}
53   // Before symbol was garbage collected too early, and we lost the constraints.
54   if (c.value != 42)
55     return;
56 
57   clang_analyzer_warnIfReached(); // no-warning: Dead code.
58 };
59 
ptr1(List * n)60 void ptr1(List* n) {
61   List* n2 = new List(*n); // ctor
62   if (!n->next) {
63     if (n2->next) {
64       clang_analyzer_warnIfReached(); // unreachable
65     }
66   }
67   delete n2;
68 }
69 
ptr2(List * n)70 void ptr2(List* n) {
71   List* n2 = new List(); // ctor
72   *n2 = *n; // assignment
73   if (!n->next) {
74     if (n2->next) {
75       clang_analyzer_warnIfReached(); // unreachable
76     }
77   }
78   delete n2;
79 }
80 
81 struct Wrapper {
82   List head;
83   int count;
84 };
85 
nestedLazyCompoundVal(List * n)86 void nestedLazyCompoundVal(List* n) {
87   Wrapper* w = 0;
88   {
89      Wrapper lw;
90      lw.head = *n;
91      w = new Wrapper(lw);
92   }
93   if (!n->next) {
94     if (w->head.next) {
95       // Unreachable, w->head is a copy of *n, therefore
96       // w->head.next and n->next are equal
97       clang_analyzer_warnIfReached(); // no-warning: unreachable
98     }
99   }
100   delete w;
101 }
102