1 // RUN: %clang_analyze_cc1 -x c++ -analyzer-checker=core -analyzer-output=text -verify %s
2
3 typedef unsigned char uint8_t;
4
5 #define UINT8_MAX 255
6 #define TCP_MAXWIN 65535
7
get_uint8_max()8 uint8_t get_uint8_max() {
9 uint8_t rcvscale = UINT8_MAX; // expected-note{{'rcvscale' initialized to 255}}
10 return rcvscale; // expected-note{{Returning the value 255 (loaded from 'rcvscale')}}
11 }
12
shift_by_undefined_value()13 void shift_by_undefined_value() {
14 uint8_t shift_amount = get_uint8_max(); // expected-note{{'shift_amount' initialized to 255}}
15 // expected-note@-1{{Calling 'get_uint8_max'}}
16 // expected-note@-2{{Returning from 'get_uint8_max'}}
17 (void)(TCP_MAXWIN << shift_amount); // expected-warning{{The result of the left shift is undefined due to shifting by '255', which is greater or equal to the width of type 'int'}}
18 // expected-note@-1{{The result of the left shift is undefined due to shifting by '255', which is greater or equal to the width of type 'int'}}
19 }
20
21 namespace array_index_tracking {
22 void consume(int);
23
getIndex(int x)24 int getIndex(int x) {
25 int a;
26 if (x > 0) // expected-note {{Assuming 'x' is > 0}}
27 // expected-note@-1 {{Taking true branch}}
28 a = 3; // expected-note {{The value 3 is assigned to 'a'}}
29 else
30 a = 2;
31 return a; // expected-note {{Returning the value 3 (loaded from 'a')}}
32 }
33
34 int getInt();
35
testArrayIndexTracking()36 void testArrayIndexTracking() {
37 int arr[10];
38
39 for (int i = 0; i < 3; ++i)
40 // expected-note@-1 3{{Loop condition is true. Entering loop body}}
41 // expected-note@-2 {{Loop condition is false. Execution continues on line 43}}
42 arr[i] = 0;
43 int x = getInt();
44 int n = getIndex(x); // expected-note {{Calling 'getIndex'}}
45 // expected-note@-1 {{Returning from 'getIndex'}}
46 // expected-note@-2 {{'n' initialized to 3}}
47 consume(arr[n]);
48 // expected-note@-1 {{1st function call argument is an uninitialized value}}
49 // expected-warning@-2{{1st function call argument is an uninitialized value}}
50 }
51 } // end of namespace array_index_tracking
52
53 namespace multi_array_index_tracking {
54 void consume(int);
55
getIndex(int x)56 int getIndex(int x) {
57 int a;
58 if (x > 0) // expected-note {{Assuming 'x' is > 0}}
59 // expected-note@-1 {{Taking true branch}}
60 a = 3; // expected-note {{The value 3 is assigned to 'a'}}
61 else
62 a = 2;
63 return a; // expected-note {{Returning the value 3 (loaded from 'a')}}
64 }
65
66 int getInt();
67
testArrayIndexTracking()68 void testArrayIndexTracking() {
69 int arr[2][10];
70
71 for (int i = 0; i < 3; ++i)
72 // expected-note@-1 3{{Loop condition is true. Entering loop body}}
73 // expected-note@-2 {{Loop condition is false. Execution continues on line 75}}
74 arr[1][i] = 0;
75 int x = getInt();
76 int n = getIndex(x); // expected-note {{Calling 'getIndex'}}
77 // expected-note@-1 {{Returning from 'getIndex'}}
78 // expected-note@-2 {{'n' initialized to 3}}
79 consume(arr[1][n]);
80 // expected-note@-1 {{1st function call argument is an uninitialized value}}
81 // expected-warning@-2{{1st function call argument is an uninitialized value}}
82 }
83 } // end of namespace mulit_array_index_tracking
84