Fix unreachable code warning in range formatter - #4932
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| if FMT_CONSTEXPR20 (range_format_kind<R, Char>::value == range_format::set) | ||
| range_formatter_.set_brackets(detail::string_literal<Char, '{'>{}, | ||
| detail::string_literal<Char, '}'>{}); |
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Since this is now a multiline-statement, please add braces around the if body.
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Fixes #4930.
The range formatter constructor returned from a compile-time branch for every
non-set range, leaving the bracket customization after the return. New MSVC
versions diagnose that statement as unreachable when sequence range formatters
are instantiated.
Invert the condition and only customize brackets for set ranges. This preserves
the behavior for both pre-C++20 and C++20 builds while allowing
if constexprto discard the unused branch.
Testing:
/W4: theranges.hC4702 warning reproduced before the changeand is absent after it
ranges-testpassedchrono-test.localeandunicode-test.legacy_localefail under this machine's zh-CN locale