<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/62123>62123</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [clang-tidy] False positive with cppcoreguidelines-narrowing-conversions from a comparison operator.
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            new issue
      </td>
    </tr>

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

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

<pre>
    On macOS, the `BOOL` type is a `signed char`, which results in some narrowing conversion warnings.

test.c:
```c
typedef signed char BOOL;

BOOL foo(int i) {
    BOOL result = (i == 0);
    return result;
}
```

Running (clang-tidy 16.0.1):

```
clang-tidy -checks=cppcoreguidelines-narrowing-conversions test.c
```

Result:

```console
test.c:4:19: warning: narrowing conversion from 'int' to signed type 'BOOL' (aka 'signed char') is implementation-defined [cppcoreguidelines-narrowing-conversions]
    BOOL result = (i == 0);
                  ^
```

In C++, a similar warning:
```console
test.cc:4:19: warning: narrowing conversion from 'bool' to signed type 'BOOL' (aka 'signed char') is implementation-defined [cppcoreguidelines-narrowing-conversions]
    BOOL result = (i == 0);
 ^
```


</pre>
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