Fixed all clang -Wsigned-enum-bitfield warnings #2882
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seanm
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include/fmt/core.h
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| @@ -2029,14 +2029,20 @@ template <typename Context> class basic_format_args { | |||
| // between clang and gcc on ARM (#1919). | |||
| using format_args = basic_format_args<format_context>; | |||
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| // We cannot use enum classes as bit fields because of a gcc bug | |||
| // We cannot use enum classes as bit fields because of a gcc bug before 9.3 | |||
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The issue with pre-9.3 gcc version seems to be about underlying types rather than enum classes because we don't use the former in both branches below. So the part about 9.3 should probably not be folded in the original comment which belongs in front of namespace align to explain why we use namespace + enum instead of scoped enums.
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I'm not so sure they are different bugs in fact. But in any case I've improved both the comments in the code and the commit message.
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Could you provide a repro (ideally a gobolt link) for future reference. |
There's one in the previous PR: #2801 (comment) here: https://godbolt.org/z/58aEv8zEq Or do you mean to add that link in the code comments? |
No, I meant in the description of this PR so that it contains all the relevant info. |
Made enums involved in bitfields unsigned by specifying their underlying type as unsigned char. Due to a bug, when specifying an underlying type, gcc < 9.3 warns about bitfields not being big enough to hold the enum, even though they are. So keep the plain enum for old gcc. An example of the bug is here: https://godbolt.org/z/58aEv8zEq
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Merged, thank you! |
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@vitaut any chance there is a release / tag coming soon? These warnings I fixed I'd like to integrate into another project I work on, but they prefer to reference official tags / releases of their upstream projects (like fmtlib)... |
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Yes by some definition of "soon". I don't have any specific dates though. |
Made enums involved in bitfields unsigned by specifying their underlying type as unsigned char.
Due to a bug, when specifying an underlying type, gcc < 9.3 warns about bitfields not being big enough to hold the enum, even though they are. So keep the plain enum for old gcc.
An example of the bug is here:
https://godbolt.org/z/58aEv8zEq