| Issue |
179458
|
| Summary |
performance-inefficient-vector-operation false-negatives when looping on multiple vectors
|
| Labels |
new issue
|
| Assignees |
|
| Reporter |
nick-potenski
|
When a loop performs inefficient operations on multiple vectors, performance-inefficient-vector-operation does not emit a warning.
```c++
#include <vector>
int main() {
std::vector<int> bob;
std::vector<float> tom;
for (auto x = 0; x < 100; x++) {
bob.emplace_back(x);
tom.push_back(x);
}
}
```
does not emit any warnings. However, commenting out one or the other vectors from the same code does:
```c++
#include <vector>
int main() {
// std::vector<int> bob;
std::vector<float> tom;
for (auto x = 0; x < 100; x++) {
// bob.emplace_back(x);
tom.push_back(x);
}
}
```
```
<source>:9:9: warning: 'push_back' is called inside a loop; consider pre-allocating the container capacity before the loop [performance-inefficient-vector-operation]
7 | for (auto x = 0; x < 100; x++) {
8 | // bob.emplace_back(x);
9 | tom.push_back(x);
| ^
1 warning generated.
```
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