[libcxx-commits] [libcxx] [libc++] Make the body of println(FILE*) dependent on the template parameter to avoid template instantiation (PR #200996)

[Braden Ganetsky via libcxx-commits]

k3DW wrote:

I have not added a unit test for this. A minimal unit test would be very simple.

```cpp
#include <print>
int main() {}
```

Compile this file with `-ftime-trace`, and ensure that the output does not contain instantiations such as `std::basic_format_string<char>::basic_format_string<char[2]>`.

I am not familiar enough with the libc++ testing to set this up myself.

https://github.com/llvm/llvm-project/pull/200996