[libcxx-commits] [libcxx] [libc++] Rename __fwd/hash.h to __fwd/functional.h and add reference_wrapper (PR #81445)

[Louis Dionne via libcxx-commits]

================
@@ -14,9 +14,8 @@
 #include <__algorithm/replace_copy.h>
----------------
ldionne wrote:

Not attached to this file: You should update `libcxx/utils/generate_iwyu_mapping.py`, which currently contains

```
elif header == "__fwd/hash.h":
        return ["functional"]
```

Generally speaking, make sure you grep for `__fwd/hash.h` to make sure you find any stray references.

https://github.com/llvm/llvm-project/pull/81445