1 // RUN: %check_clang_tidy %s bugprone-undefined-memory-manipulation %t
2 
3 void *memset(void *, int, __SIZE_TYPE__);
4 void *memcpy(void *, const void *, __SIZE_TYPE__);
5 void *memmove(void *, const void *, __SIZE_TYPE__);
6 
7 namespace std {
8 using ::memcpy;
9 using ::memmove;
10 using ::memset;
11 }
12 
13 namespace types {
14 // TriviallyCopyable types:
15 struct Plain {
16   int n;
17 };
18 
19 enum E {
20   X,
21   Y,
22   Z
23 };
24 
25 struct Base {
26   float b;
27 };
28 
29 struct Derived : Base {
30   bool d;
31 };
32 
33 // not TriviallyCopyable types:
34 struct Destruct {
35   ~Destruct() {}
36 };
37 
38 struct Copy {
39   Copy() {}
40   Copy(const Copy &) {}
41 };
42 
43 struct Move {
44   Move() {}
45   Move(Move &&) {}
46 };
47 
48 struct VirtualFunc {
49   virtual void f() {}
50 };
51 
52 struct VirtualBase : virtual Base {
53   int vb;
54 };
55 
56 // Incomplete type, assume it is TriviallyCopyable.
57 struct NoDef;
58 
59 } // end namespace types
60 
61 void f(types::NoDef *s) {
62   memset(s, 0, 5);
63 }
64 
65 template <typename T>
66 void memset_temp(T *b) {
67   memset(b, 0, sizeof(T));
68   // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: undefined behavior, destination object type 'types::VirtualFunc' is not TriviallyCopyable [bugprone-undefined-memory-manipulation]
69 }
70 
71 template <typename S, typename T>
72 void memcpy_temp(S *a, T *b) {
73   memcpy(a, b, sizeof(T));
74   // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: undefined behavior, source object type 'types::VirtualFunc'
75 }
76 
77 template <typename S, typename T>
78 void memmove_temp(S *a, T *b) {
79   memmove(a, b, sizeof(T));
80   // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: undefined behavior, source object type 'types::VirtualFunc'
81 }
82 
83 namespace aliases {
84 using Copy2 = types::Copy;
85 typedef types::Move Move2;
86 }
87 
88 void notTriviallyCopyable() {
89   types::Plain p; // TriviallyCopyable for variety
90   types::Destruct d;
91   types::Copy c;
92   types::Move m;
93   types::VirtualFunc vf;
94   types::VirtualBase vb;
95 
96   memset(&vf, 0, sizeof(int));
97   // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: undefined behavior, destination object type 'types::VirtualFunc'
98   memset(&d, 0, sizeof(int));
99   // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: undefined behavior, destination object type 'types::Destruct'
100   memset(&c, 0, sizeof(int));
101   // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: undefined behavior, destination object type 'types::Copy'
102   std::memset(&m, 0, sizeof(int));
103   // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: undefined behavior, destination object type 'types::Move'
104   ::memset(&vb, 0, sizeof(int));
105   // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: undefined behavior, destination object type 'types::VirtualBase'
106 
107   memcpy(&p, &vf, sizeof(int));
108   // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: undefined behavior, source object type 'types::VirtualFunc'
109   memcpy(&p, &d, sizeof(int));
110   // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: undefined behavior, source object type 'types::Destruct'
111   memcpy(&c, &p, sizeof(int));
112   // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: undefined behavior, destination object type 'types::Copy'
113   std::memcpy(&m, &p, sizeof(int));
114   // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: undefined behavior, destination object type 'types::Move'
115   ::memcpy(&vb, &p, sizeof(int));
116   // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: undefined behavior, destination object type 'types::VirtualBase'
117 
118   memmove(&vf, &p, sizeof(int));
119   // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: undefined behavior, destination object type 'types::VirtualFunc'
120   memmove(&d, &p, sizeof(int));
121   // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: undefined behavior, destination object type 'types::Destruct'
122   memmove(&p, &c, sizeof(int));
123   // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: undefined behavior, source object type 'types::Copy'
124   std::memmove(&p, &m, sizeof(int));
125   // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: undefined behavior, source object type 'types::Move'
126   ::memmove(&p, &vb, sizeof(int));
127   // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: undefined behavior, source object type 'types::VirtualBase'
128 
129 #define MEMSET memset(&vf, 0, sizeof(int));
130   MEMSET
131   // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: undefined behavior, destination object type 'types::VirtualFunc'
132 #define MEMCPY memcpy(&d, &p, sizeof(int));
133   MEMCPY
134   // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: undefined behavior, destination object type 'types::Destruct'
135 #define MEMMOVE memmove(&p, &c, sizeof(int));
136   MEMMOVE
137   // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: undefined behavior, source object type 'types::Copy'
138 
139   memset_temp<types::VirtualFunc>(&vf);
140   memcpy_temp<types::Plain, types::VirtualFunc>(&p, &vf);
141   memmove_temp<types::Plain, types::VirtualFunc>(&p, &vf);
142 
143   aliases::Copy2 c2;
144   aliases::Move2 m2;
145   memset(&c2, 0, sizeof(int));
146   // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: undefined behavior, destination object type 'aliases::Copy2'
147   memset(&m2, 0, sizeof(int));
148   // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: undefined behavior, destination object type 'aliases::Move2'
149 
150   typedef aliases::Copy2 Copy3;
151   typedef aliases::Copy2 *PCopy2;
152   typedef Copy3 *PCopy3;
153   Copy3 c3;
154   PCopy2 pc2;
155   PCopy3 pc3;
156   memset(&c3, 0, sizeof(int));
157   // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: undefined behavior, destination object type 'Copy3'
158   memset(pc2, 0, sizeof(int));
159   // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: undefined behavior, destination object type 'aliases::Copy2'
160   memset(pc3, 0, sizeof(int));
161   // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: undefined behavior, destination object type 'Copy3'
162 }
163 
164 void triviallyCopyable() {
165   types::Plain p;
166   types::Base base;
167   types::Derived derived;
168 
169   int i = 5;
170   int ia[3] = {1, 2, 3};
171   float f = 3.14;
172   float fa[3] = {1.1, 2.2, 3.3};
173   bool b = false;
174   bool ba[2] = {true, false};
175   types::E e = types::X;
176   p.n = 2;
177 
178   memset(&p, 0, sizeof(int));
179   memset(&base, 0, sizeof(float));
180   memset(&derived, 0, sizeof(bool));
181   memset(&i, 0, sizeof(int));
182   memset(ia, 0, sizeof(int));
183   memset(&f, 0, sizeof(float));
184   memset(fa, 0, sizeof(float));
185   memset(&b, 0, sizeof(bool));
186   memset(ba, 0, sizeof(bool));
187   memset(&e, 0, sizeof(int));
188   memset(&p.n, 0, sizeof(int));
189 
190   memcpy(&p, &p, sizeof(int));
191   memcpy(&base, &base, sizeof(float));
192   memcpy(&derived, &derived, sizeof(bool));
193   memcpy(&i, &i, sizeof(int));
194   memcpy(ia, ia, sizeof(int));
195   memcpy(&f, &f, sizeof(float));
196   memcpy(fa, fa, sizeof(float));
197   memcpy(&b, &b, sizeof(bool));
198   memcpy(ba, ba, sizeof(bool));
199   memcpy(&e, &e, sizeof(int));
200   memcpy(&p.n, &p.n, sizeof(int));
201 
202   memmove(&p, &p, sizeof(int));
203   memmove(&base, &base, sizeof(float));
204   memmove(&derived, &derived, sizeof(bool));
205   memmove(&i, &i, sizeof(int));
206   memmove(ia, ia, sizeof(int));
207   memmove(&f, &f, sizeof(float));
208   memmove(fa, fa, sizeof(float));
209   memmove(&b, &b, sizeof(bool));
210   memmove(ba, ba, sizeof(bool));
211   memmove(&e, &e, sizeof(int));
212   memmove(&p.n, &p.n, sizeof(int));
213 }
214