libstdc++-v3/ChangeLog:

	* src/c++17/fast_float/LOCAL_PATCHES: Update.

This patch resolves the GCC compilation issue for the C++ language
targeting aarch64-w64-mingw32.

The change in fast_float has been upstreamed.
https://github.com/fastfloat/fast_float/pull/269

libstdc++-v3/ChangeLog:

	* src/c++17/fast_float/fast_float.h (full_multiplication):
	Support aarch64-w64-mingw32 target.

Upstream fast_float came up with a cheaper test for
fegetround () == FE_TONEAREST using one float addition, one subtraction
and one comparison.  If we know we are rounding to nearest, we can use
fast path in more cases as before.
The following patch merges those changes into libstdc++.

2022-11-24  Jakub Jelinek  <jakub@redhat.com>

	PR libstdc++/107468
	* src/c++17/fast_float/MERGE: Adjust for merge from upstream.
	* src/c++17/fast_float/fast_float.h: Merge from fast_float
	2ef9abbcf6a11958b6fa685a89d0150022e82e78 commit.

The following patch updates from fast_float trunk.  That way
it grabs two of the 4 LOCAL_PATCHES, some smaller tweaks, to_extended
cleanups and most importantly fix for the incorrect rounding case,
PR107468 aka https://github.com/fastfloat/fast_float/issues/149
Using std::fegetround showed in benchmarks too slow, so instead of
doing that the patch limits the fast path where it uses floating
point multiplication rather than integral to cases where we can
prove there will be no rounding (the multiplication will be exact, not
just that the two multiplication or division operation arguments are
exactly representable).

2022-11-07  Jakub Jelinek  <jakub@redhat.com>

	PR libstdc++/107468
	* src/c++17/fast_float/MERGE: Adjust for merge from upstream.
	* src/c++17/fast_float/LOCAL_PATCHES: Remove commits that were
	upstreamed.
	* src/c++17/fast_float/README.md: Merge from fast_float
	662497742fea7055f0e0ee27e5a7ddc382c2c38e commit.
	* src/c++17/fast_float/fast_float.h: Likewise.
	* testsuite/20_util/from_chars/pr107468.cc: New test.

Instead of hardcoded preprocessor conditionals with explicit target
checks, just rely on the fact that __BYTE_ORDER__ is always defined by
GCC.

libstdc++-v3/ChangeLog:

	PR libstdc++/104080
	* src/c++17/fast_float/LOCAL_PATCHES: Update.
	* src/c++17/fast_float/fast_float.h (FASTFLOAT_IS_BIG_ENDIAN):
	Define in terms of __BYTE_ORDER__.

libstdc++-v3/ChangeLog:

	PR libstdc++/104080
	* src/c++17/fast_float/LOCAL_PATCHES: UPDATE.
	* src/c++17/fast_float/fast_float.h (round): Use explicit
	template argument list for std::min.

This changes fast_float's handling of overflow/underflow to be
consistent with the standard: instead of returning errc{} and setting
value to +-0 or +-infinity, just return errc::result_out_of_range and
don't modify value, as per [charconv.from.chars]/1.

libstdc++-v3/ChangeLog:

	* src/c++17/fast_float/LOCAL_PATCHES: Update.
	* src/c++17/fast_float/fast_float.h (from_chars_advanced): In
	case of over/underflow, return errc::result_out_of_range and don't
	modify 'value'.

This performs the following modifications to our local copy of fast_float
in order to make it more readily usable in our std::from_chars
implementation:

  * Remove system #includes
  * Replace stray call to assert
  * Use the standard chars_format and from_chars_result types

libstdc++-v3/ChangeLog:

	* src/c++17/fast_float/LOCAL_PATCHES: Update.
	* src/c++17/fast_float/fast_float.h: Apply local modifications.

We're going to use the fast_float library[1] in our (compiled-in)
floating-point std::from_chars implementation for faster and more
portable parsing of binary32/64 decimal strings.

The single file fast_float.h is an amalgamation of the entire library,
which can be (re)generated with the amalgamate.py script (from the
fast_float repository) via the command

  python3 ./script/amalgamate.py --license=MIT \
    > $GCC_SRC/libstdc++-v3/c++17/fast_float/fast_float.h

The code has a GPL-compatible license.

[1]: https://github.com/fastfloat/fast_float

libstdc++-v3/ChangeLog:

	* src/c++17/fast_float/LOCAL_PATCHES: New file.
	* src/c++17/fast_float/MERGE: New file.
	* src/c++17/fast_float/README.md: New file, copied from the
	fast_float repository.
	* src/c++17/fast_float/fast_float.h: New file, an amalgamation
	of the fast_float library.

Signed-off-by: Patrick Palka <ppalka@redhat.com>