[libc++] Implements LWG3130. (#101889)

This adds addressof at the required places in [input.output]. Some of
the new tests failed since string used operator& internally. These have
been fixed too.

[libc++] Implements LWG3130. (#101889)

This adds addressof at the required places in [input.output]. Some of
the new tests failed since string used operator& internally. These have
been fixed too.

Note the new fstream tests perform output to a basic_string instead of a
double. Using a double requires num_get specialization

num_get<CharT, istreambuf_iterator<CharT,
char_traits_operator_hijacker<CharT>>

This facet is not present in the locale database so the conversion would
fail due to a missing locale facet. Using basic_string avoids using the
locale.

As a drive-by fixes several bugs in the ofstream.cons tests. These
tested ifstream instead of ofstream with an open mode.

Implements:
- LWG3130 [input.output] needs many addressof

Closes #100246.

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[ASan][libc++] std::basic_string annotations (#72677)

This commit introduces basic annotations for `std::basic_string`,
mirroring the approach used in `std::vector` and `std::deque`.
Initially, on

[ASan][libc++] std::basic_string annotations (#72677)

This commit introduces basic annotations for `std::basic_string`,
mirroring the approach used in `std::vector` and `std::deque`.
Initially, only long strings with the default allocator will be
annotated. Short strings (_SSO - short string optimization_) and strings
with non-default allocators will be annotated in the near future, with
separate commits dedicated to enabling them. The process will be similar
to the workflow employed for enabling annotations in `std::deque`.

**Please note**: these annotations function effectively only when libc++
and libc++abi dylibs are instrumented (with ASan). This aligns with the
prevailing behavior of Memory Sanitizer.

To avoid breaking everything, this commit also appends
`_LIBCPP_INSTRUMENTED_WITH_ASAN` to `__config_site` whenever libc++ is
compiled with ASan. If this macro is not defined, string annotations are
not enabled. However, linking a binary that does **not** annotate
strings with a dynamic library that annotates strings, is not permitted.

Originally proposed here: https://reviews.llvm.org/D132769

Related patches on Phabricator:
- Turning on annotations for short strings:
https://reviews.llvm.org/D147680
- Turning on annotations for all allocators:
https://reviews.llvm.org/D146214

This PR is a part of a series of patches extending AddressSanitizer C++
container overflow detection capabilities by adding annotations, similar
to those existing in `std::vector` and `std::deque` collections. These
enhancements empower ASan to effectively detect instances where the
instrumented program attempts to access memory within a collection's
internal allocation that remains unused. This includes cases where
access occurs before or after the stored elements in `std::deque`, or
between the `std::basic_string`'s size (including the null terminator)
and capacity bounds.

The introduction of these annotations was spurred by a real-world
software bug discovered by Trail of Bits, involving an out-of-bounds
memory access during the comparison of two strings using the
`std::equals` function. This function was taking iterators
(`iter1_begin`, `iter1_end`, `iter2_begin`) to perform the comparison,
using a custom comparison function. When the `iter1` object exceeded the
length of `iter2`, an out-of-bounds read could occur on the `iter2`
object. Container sanitization, upon enabling these annotations, would
effectively identify and flag this potential vulnerability.

This Pull Request introduces basic annotations for `std::basic_string`.
Long strings exhibit structural similarities to `std::vector` and will
be annotated accordingly. Short strings are already implemented, but
will be turned on separately in a forthcoming commit. Look at [a
comment](https://github.com/llvm/llvm-project/pull/72677#issuecomment-1850554465)
below to read about SSO issues at current moment.

Due to the functionality introduced in
[D132522](https://github.com/llvm/llvm-project/commit/dd1b7b797a116eed588fd752fbe61d34deeb24e4),
the `__sanitizer_annotate_contiguous_container` function now offers
compatibility with all allocators. However, enabling this support will
be done in a subsequent commit. For the time being, only strings with
the default allocator will be annotated.

If you have any questions, please email:
- advenam.tacet@trailofbits.com
- disconnect3d@trailofbits.com

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[libc++][test] Add missing include

`std::out_of_range` is in `<stdexcept>`

[libc++] Implement P2438R2 (std::string::substr() &&)

This doesn't affect our ABI because `std::string::substr()` isn't in the dylib and the mangling of `substr() const` and `substr() const&` are di

[libc++] Implement P2438R2 (std::string::substr() &&)

This doesn't affect our ABI because `std::string::substr()` isn't in the dylib and the mangling of `substr() const` and `substr() const&` are different.

Reviewed By: ldionne, Mordante, var-const, avogelsgesang, #libc

Spies: arphaman, huixie90, libcxx-commits

Differential Revision: https://reviews.llvm.org/D131668

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