to_chars libc++ compatibility

[mordante]

@StephanTLavavej here some changes I made in libc++ for https://reviews.llvm.org/D70631 "Microsoft's floating-point to_chars powered by Ryu and Ryu Printf". If you don't like _Output feel free to suggest an alternative and I'll adjust libc++ accordingly.

[ghost]

All CLA requirements met.

[mordante]

I also notices line 1103 and 1105 look oddly similar in their suggestion "Consider retuning PrefixesToTest and FractionBits.". I suspect that's not intended. Both also have a small typo in "returning".

[StephanTLavavej]

I also notices line 1103 and 1105 look oddly similar in their suggestion "Consider retuning PrefixesToTest and FractionBits.". I suspect that's not intended. Both also have a small typo in "returning".

STL/tests/std/tests/P0067R5_charconv/test.cpp

Lines 1100 to 1104 in 834baa6

	if (ms < 3'000) {
	puts("That was fast. Consider retuning PrefixesToTest and FractionBits.");
	} else if (ms > 30'000) {
	puts("That was slow. Consider retuning PrefixesToTest and FractionBits.");
	}

It was intentional, although I can see now how it could be confusing. By "retuning" I meant "re-tuning", and the similar messages were intended to say "if this test ran really fast, you should probably be testing more random values" and "if this test ran really slow, you should probably test fewer random values". I can clarify this.

[StephanTLavavej]

Looks good to me! I've pushed two small commits, one to restore indentation (clang-format is disabled for the Ryu-derived code so it can stay somewhat consistent with upstream, otherwise it would have detected the extra space) and another to clarify the fast/slow comments (also in another test that had used the same wording).

Our system involves 2 reviews before simultaneously merging to GitHub and the MSVC-internal repo, so we should be able to get a second reviewer and batch this up for merging early next week.

[mordante]

Looks good to me! I've pushed two small commits, one to restore indentation (clang-format is disabled for the Ryu-derived code so it can stay somewhat consistent with upstream, otherwise it would have detected the extra space) and another to clarify the fast/slow comments (also in another test that had used the same wording).

The new wording looks clearer, thanks.

Our system involves 2 reviews before simultaneously merging to GitHub and the MSVC-internal repo, so we should be able to get a second reviewer and batch this up for merging early next week.

Great, once it has landed I'll sync the code in libc++.

[StephanTLavavej]

Thanks for keeping our codebases aligned, and congratulations on your first microsoft/STL commit! 😸 🎉 🎆