<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/115743>115743</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [clang-tidy] False-positive with returning a constant reference parameter.
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            clang-tidy
      </td>
    </tr>

    <tr>
      <th>Assignees</th>
      <td>
      </td>
    </tr>

    <tr>
      <th>Reporter</th>
      <td>
          Jhuighuy
      </td>
    </tr>
</table>

<pre>
    Hi everyone,

Consider the following snippet of code:

```cpp
#include <array>

template<class T>
void f(const T& t) {
    const auto get = [&t] -> const T& { return t; };
 return std::array{get(), get(), get()};
}
```

When I run the latest released `clang-tidy` (19.1.3) over it with a check `bugprone-return-const-ref-from-parameter`, it produces a false-positive warning:

```
$ clang-tidy --version 
Homebrew LLVM version 19.1.3
  Optimized build.
$ clang-tidy b.cpp "--checks=bugprone-return-const-ref-from-parameter" -- -std=c++23                                                      
1 warning generated.
.../b.cpp:5:45: warning: returning a constant reference parameter may cause use-after-free when the parameter is constructed from a temporary [bugprone-return-const-ref-from-parameter]
    5 |         const auto get = [&t] -> const T& { return t; };
      | 
```

Clearly, `t` is not returned from the function `f`, and it not a parameter of a lambda.
</pre>
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