<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/135558>135558</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            misleading fix-it with `bugprone-unintended-char-ostream-output` in templated code
        </td>
    </tr>

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

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

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

<pre>
    The fix-it is problematic if it is a templated type and should probably be omitted in that case:
```cpp
#include <cstdint>
#include <sstream>

template<typename T>
void func(const T& data)
{
 std::ostringstream ostr;
    ostr << data;
}

void f()
{
 func((char)0);
    func((int8_t)0);
 func("");
}
```

```
<source>:8:10: warning: 'signed char' passed to 'operator<<' outputs as character instead of integer. cast to 'unsigned int' to print numeric value or cast to 'char' to print as character [bugprone-unintended-char-ostream-output]
    8 |     ostr << data;
 |          ^  ~~~~
      | static_cast<int>(data)
```
https://godbolt.org/z/93axK1E4M

_Originally posted by @firewave in https://github.com/llvm/llvm-project/issues/127720#issuecomment-2729734197_
 
</pre>
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