<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/146294>146294</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [clang-tidy] Check request: misc-no-template-recursion
        </td>
    </tr>

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

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

    <tr>
      <th>Reporter</th>
      <td>
          denzor200
      </td>
    </tr>
</table>

<pre>
    clang-tidy already has [misc-no-recursion](https://clang.llvm.org/extra/clang-tidy/checks/misc/no-recursion.html) check that detects recursive function calls in non-template code. However, in C++, recursion can also occur at compile time, via recursive template instantiation, which can lead to:
- Significantly increased compilation time;
- Inflated binary file size due to multiple instantiations;
- Compiler stack overflow.

Need a check that will discover direct and indirect recursion in templates.

Example direct:
```
template<int N> struct Factorial {
    static const int value = N * Factorial<N-1>::value;  // BAD
};
```

Example indirect (B → C → B): 
```
template<typename T> struct B { using Type = typename C<T>::Type; };   // BAD
template<typename T> struct C { using Type = typename B<T>::Type; };   // BAD 
```

All the samples above were simplified to not have the base case.


</pre>
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