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<tr>
<th>Issue</th>
<td>
<a href=https://github.com/llvm/llvm-project/issues/64522>64522</a>
</td>
</tr>
<tr>
<th>Summary</th>
<td>
[Bug]: Issues with `std::format`, `std::vformat` in `libcxx`
</td>
</tr>
<tr>
<th>Labels</th>
<td>
</td>
</tr>
<tr>
<th>Assignees</th>
<td>
</td>
</tr>
<tr>
<th>Reporter</th>
<td>
just-ero
</td>
</tr>
</table>
<pre>
## Description
Using parts of `std::format` and `std::vformat` results in issues in `format_arg_store.h`. I don't have a minimal repro unfortunately.
Here are some of the errors I see:
```
~/libcxx/include/__format/format_arg_store.h(158,29): error : call to deleted function '__determine_arg_t'
~/libcxx/include/__format/format_arg_store.h(158,21): error : constexpr variable '__arg' must be initialized by a constant expression
~/libcxx/include/__format/format_arg_store.h(158,29): error : call to consteval function 'std::__format::__determine_arg_t<std::format_context, unsigned int *>' is not a constant expression
~/libcxx/include/__format/format_arg_store.h(159,17): error : static assertion expression is not an integral constant expression
~/libcxx/include/__format/format_arg_store.h(164,17): error : constexpr if condition is not a constant expression
~/libcxx/include/__format/format_arg_store.h(167,46): error : static_cast from 'unsigned int *' to 'typename format_context::char_type' (aka 'char') is not allowed
```
There are no errors resulting from my own code (none in my own files).
</pre>
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