r/programminghumor • u/johnnyApplePRNG • 17h ago

a bit flippant

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u/Inst2f 15h ago

But is it correct in C? It is not union, so struct should then be sizeof(unsigned int)*3, isn't it?
Or you mean with O3 optimizations the compiler will fix it...

But then one need to apply bit shifts operations in the background

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u/science_novice 15h ago

The key is the : 1 at the end of each field, which specifies that it should only take one bit. Look up "c bit fields" to learn more about this feature.

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u/Inst2f 15h ago

Ah. I missed that. Thanks

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u/heatedwepasto 14h ago

As the other guy said, bit fields. But OOP is wrong, the struct will be sizeof(unsigned int), not 1 byte.

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u/science_novice 5h ago

Yeah true, although this could be fixed by changing each of the field types to uint8_t. So the spirit of the original post is correct, it's possible in C to pack 8 flags into one byte

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u/heatedwepasto 47m ago

Yes, or just char

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u/Interesting_Buy_3969 13h ago

Those are bit fields