<bitset>: Make bitset::all work like bitset::any

[AlexGuteniev]

Description

Fix #669

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[AlexGuteniev]

The test are failed due to warning:

3: C:\agent\_work\1\a\x64\out\inc\bitset(403): error C2220: the following warning is treated as an error
3: C:\agent\_work\1\a\x64\out\inc\bitset(403): warning C4127: conditional expression is constant
3: C:\agent\_work\1\a\x64\out\inc\bitset(403): note: consider using 'if constexpr' statement instead
3: C:\agent\_work\1\a\x64\out\inc\bitset(402): note: while compiling class template member function 'bool std::bitset<5>::all(void) noexcept const'
3: C:\agent\_work\1\s\tests\tr1\tests\bitset\test.cpp(82): note: see reference to function template instantiation 'bool std::bitset<5>::all(void) noexcept const' being compiled
3: C:\agent\_work\1\s\tests\tr1\tests\bitset\test.cpp(13): note: see reference to class template instantiation 'std::bitset<5>' being compiled
3: C:\agent\_work\1\a\x64\out\inc\bitset(411): warning C4127: conditional expression is constant
3: C:\agent\_work\1\a\x64\out\inc\bitset(411): note: consider using 'if constexpr' statement instead

I can suppress them locally, but maybe need to embed suppression to _CONSTEXPR_IF?

[StephanTLavavej]

Looks good, just minor nitpicks. Thanks!

[StephanTLavavej]

I can suppress them locally, but maybe need to embed suppression to _CONSTEXPR_IF?

That's an interesting idea - I hadn't considered embedding a _Pragma into that macro, but if it works, it would resolve most of our local C4127 suppressions!

[CaseyCarter]

I can suppress them locally, but maybe need to embed suppression to _CONSTEXPR_IF?

That's an interesting idea - I hadn't considered embedding a _Pragma into that macro, but if it works, it would resolve most of our local C4127 suppressions!

We've been using the

constexpr bool _Meow = /* some constant expression */;
if _CONSTEXPR_IF (_Meow) {

trick to avoid C4127 in newer code rather than suppressing it. The only suppressions are in "old" things that probably aren't using if constexpr or if _CONSTEXPR_IF.

[AlexGuteniev]

I assume that _Pragma("warning(suppress : N)") would work.

I recall __pragma(warning(suppress : N)) worked in VS2005 or VS2008.
It had some problems on duration of its effect when statement ends not in next line - in some cases suppression lasted unexpectedly long (by a line or two off). I'm afraid I can't prove this claim with repro, it has been ten years, so I rather hope it is fixed.

Anyway, I'll follow what @CaseyCarter suggests.

[StephanTLavavej]

Looks great, thanks!

[CaseyCarter]

Thanks for the improvement!