1// RUN: %check_clang_tidy %s bugprone-misplaced-widening-cast %t -- -config="{CheckOptions: {bugprone-misplaced-widening-cast.CheckImplicitCasts: true}}" --
2
3void func(long arg) {}
4
5void assign(int a, int b) {
6 long l;
7
8 l = a * b;
9 // CHECK-MESSAGES: :[[@LINE-1]]:7: warning: either cast from 'int' to 'long' is ineffective, or there is loss of precision before the conversion [bugprone-misplaced-widening-cast]
10 l = (long)(a * b);
11 // CHECK-MESSAGES: :[[@LINE-1]]:7: warning: either cast from 'int' to 'long'
12 l = (long)a * b;
13
14 l = a << 8;
15 // CHECK-MESSAGES: :[[@LINE-1]]:7: warning: either cast from 'int' to 'long'
16 l = (long)(a << 8);
17 // CHECK-MESSAGES: :[[@LINE-1]]:7: warning: either cast from 'int' to 'long'
18 l = (long)b << 8;
19
20 l = static_cast<long>(a * b);
21 // CHECK-MESSAGES: :[[@LINE-1]]:7: warning: either cast from 'int' to 'long'
22}
23
24void compare(int a, int b, long c) {
25 bool l;
26
27 l = a * b == c;
28 // CHECK-MESSAGES: :[[@LINE-1]]:7: warning: either cast from 'int' to 'long'
29 l = c == a * b;
30 // CHECK-MESSAGES: :[[@LINE-1]]:12: warning: either cast from 'int' to 'long'
31 l = (long)(a * b) == c;
32 // CHECK-MESSAGES: :[[@LINE-1]]:7: warning: either cast from 'int' to 'long'
33 l = c == (long)(a * b);
34 // CHECK-MESSAGES: :[[@LINE-1]]:12: warning: either cast from 'int' to 'long'
35 l = (long)a * b == c;
36 l = c == (long)a * b;
37}
38
39void init(unsigned int n) {
40 long l1 = n << 8;
41 // CHECK-MESSAGES: :[[@LINE-1]]:13: warning: either cast from 'unsigned int' to 'long'
42 long l2 = (long)(n << 8);
43 // CHECK-MESSAGES: :[[@LINE-1]]:13: warning: either cast from 'unsigned int' to 'long'
44 long l3 = (long)n << 8;
45}
46
47void call(unsigned int n) {
48 func(arg: n << 8);
49 // CHECK-MESSAGES: :[[@LINE-1]]:8: warning: either cast from 'unsigned int' to 'long'
50 func(arg: (long)(n << 8));
51 // CHECK-MESSAGES: :[[@LINE-1]]:8: warning: either cast from 'unsigned int' to 'long'
52 func(arg: (long)n << 8);
53}
54
55long ret(int a) {
56 if (a < 0) {
57 return a * 1000;
58 // CHECK-MESSAGES: :[[@LINE-1]]:12: warning: either cast from 'int' to 'long'
59 } else if (a > 0) {
60 return (long)(a * 1000);
61 // CHECK-MESSAGES: :[[@LINE-1]]:12: warning: either cast from 'int' to 'long'
62 } else {
63 return (long)a * 1000;
64 }
65}
66
67void dontwarn1(unsigned char a, int i, unsigned char *p) {
68 long l;
69 // The result is a 9 bit value, there is no truncation in the implicit cast.
70 l = (long)(a + 15);
71 // The result is a 12 bit value, there is no truncation in the implicit cast.
72 l = (long)(a << 4);
73 // The result is a 3 bit value, there is no truncation in the implicit cast.
74 l = (long)((i % 5) + 1);
75 // The result is a 16 bit value, there is no truncation in the implicit cast.
76 l = (long)(((*p) << 8) + *(p + 1));
77}
78
79template <class T> struct DontWarn2 {
80 void assign(T a, T b) {
81 long l;
82 l = (long)(a * b);
83 }
84};
85DontWarn2<int> DW2;
86
87// Cast is not suspicious when casting macro.
88#define A (X<<2)
89long macro1(int X) {
90 return (long)A;
91}
92
93// Don't warn about cast in macro.
94#define B(X,Y) (long)(X*Y)
95long macro2(int x, int y) {
96 return B(x,y);
97}
98
99void floatingpoint(float a, float b) {
100 double d = (double)(a * b); // Currently we don't warn for this.
101}
102

source code of clang-tools-extra/test/clang-tidy/checkers/bugprone/misplaced-widening-cast-implicit-enabled.cpp