1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
| // RUN: %check_clang_tidy %s bugprone-fold-init-type %t
namespace std {
template <class InputIt, class T>
T accumulate(InputIt first, InputIt last, T init);
template <class InputIt, class T>
T reduce(InputIt first, InputIt last, T init);
template <class ExecutionPolicy, class InputIt, class T>
T reduce(ExecutionPolicy &&policy,
InputIt first, InputIt last, T init);
struct parallel_execution_policy {};
constexpr parallel_execution_policy par{};
template <class InputIt1, class InputIt2, class T>
T inner_product(InputIt1 first1, InputIt1 last1,
InputIt2 first2, T value);
template <class ExecutionPolicy, class InputIt1, class InputIt2, class T>
T inner_product(ExecutionPolicy &&policy, InputIt1 first1, InputIt1 last1,
InputIt2 first2, T value);
} // namespace std
struct FloatIterator {
typedef float value_type;
};
template <typename ValueType>
struct TypedefTemplateIterator { typedef ValueType value_type; };
template <typename ValueType>
struct UsingTemplateIterator { using value_type = ValueType; };
template <typename ValueType>
struct DependentTypedefTemplateIterator { typedef typename ValueType::value_type value_type; };
template <typename ValueType>
struct DependentUsingTemplateIterator : public TypedefTemplateIterator<ValueType> { using typename TypedefTemplateIterator<ValueType>::value_type; };
using TypedeffedIterator = FloatIterator;
// Positives.
int accumulatePositive1() {
float a[1] = {0.5f};
return std::accumulate(a, a + 1, 0);
// CHECK-MESSAGES: [[@LINE-1]]:10: warning: folding type 'float' into type 'int'
}
int accumulatePositive2() {
FloatIterator it;
return std::accumulate(it, it, 0);
// CHECK-MESSAGES: [[@LINE-1]]:10: warning: folding type 'float' into type 'int'
}
int accumulatePositive3() {
double a[1] = {0.0};
return std::accumulate(a, a + 1, 0.0f);
// CHECK-MESSAGES: [[@LINE-1]]:10: warning: folding type 'double' into type 'float'
}
int accumulatePositive4() {
TypedefTemplateIterator<unsigned> it;
return std::accumulate(it, it, 0);
// CHECK-MESSAGES: [[@LINE-1]]:10: warning: folding type 'unsigned int' into type 'int'
}
int accumulatePositive5() {
UsingTemplateIterator<unsigned> it;
return std::accumulate(it, it, 0);
// CHECK-MESSAGES: [[@LINE-1]]:10: warning: folding type 'unsigned int' into type 'int'
}
int accumulatePositive6() {
DependentTypedefTemplateIterator<UsingTemplateIterator<unsigned>> it;
return std::accumulate(it, it, 0);
// CHECK-MESSAGES: [[@LINE-1]]:10: warning: folding type 'unsigned int' into type 'int'
}
int accumulatePositive7() {
TypedeffedIterator it;
return std::accumulate(it, it, 0);
// CHECK-MESSAGES: [[@LINE-1]]:10: warning: folding type 'float' into type 'int'
}
int accumulatePositive8() {
DependentUsingTemplateIterator<unsigned> it;
return std::accumulate(it, it, 0);
// FIXME: this one should trigger too.
}
int reducePositive1() {
float a[1] = {0.5f};
return std::reduce(a, a + 1, 0);
// CHECK-MESSAGES: [[@LINE-1]]:10: warning: folding type 'float' into type 'int'
}
int reducePositive2() {
float a[1] = {0.5f};
return std::reduce(std::par, a, a + 1, 0);
// CHECK-MESSAGES: [[@LINE-1]]:10: warning: folding type 'float' into type 'int'
}
int innerProductPositive1() {
float a[1] = {0.5f};
int b[1] = {1};
return std::inner_product(std::par, a, a + 1, b, 0);
// CHECK-MESSAGES: [[@LINE-1]]:10: warning: folding type 'float' into type 'int'
}
int innerProductPositive2() {
float a[1] = {0.5f};
int b[1] = {1};
return std::inner_product(std::par, a, a + 1, b, 0);
// CHECK-MESSAGES: [[@LINE-1]]:10: warning: folding type 'float' into type 'int'
}
// Negatives.
int negative1() {
float a[1] = {0.5f};
// This is OK because types match.
return std::accumulate(a, a + 1, 0.0);
}
int negative2() {
float a[1] = {0.5f};
// This is OK because double is bigger than float.
return std::accumulate(a, a + 1, 0.0);
}
int negative3() {
float a[1] = {0.5f};
// This is OK because the user explicitly specified T.
return std::accumulate<float *, float>(a, a + 1, 0);
}
int negative4() {
TypedefTemplateIterator<unsigned> it;
// For now this is OK.
return std::accumulate(it, it, 0.0);
}
int negative5() {
float a[1] = {0.5f};
float b[1] = {1.0f};
return std::inner_product(std::par, a, a + 1, b, 0.0f);
}
namespace blah {
namespace std {
template <class InputIt, class T>
T accumulate(InputIt, InputIt, T); // We should not care about this one.
}
int negative5() {
float a[1] = {0.5f};
// Note that this is using blah::std::accumulate.
return std::accumulate(a, a + 1, 0);
}
}
|