<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/151113>151113</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [clang] Unnecessary instantiations of `constexpr` functions in `if constexpr (false)`
        </td>
    </tr>

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

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

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

<pre>
    ```cpp
template <int N>
static constexpr void f() {
    static_assert(N == 0);
}

void g() {
    if constexpr (false) {
        f<1>();
    }
}
```
This fails to compile: https://gcc.godbolt.org/z/G87rsPjWo (GCC accepts)

Removing `constexpr` from `f()` makes this compile, but it shouldn't matter either way. `f()` is not odr-used, not constant-evaluated, or otherwise needs to be instantiated.
</pre>
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