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A comment on The Byte Order Fiasco. Parent comment

Re:The Byte Order Fiasco by professoretc on Saturday May 08, 2021 @01:00PM (#27088861)
char* is a allowed to alias to other pointer types.
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Re:The Byte Order Fiasco by jeffreygoesto on Saturday May 08, 2021 @03:05PM (#27089844)
Hm. Afsik, you are always allowed to convert _to_ a char, but _from_ is not ok in general. See i.e. [0]

[0] https://gist.github.com/shafik/848ae25ee209f698763cffee272a5...

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Re:The Byte Order Fiasco by jart on Monday May 10, 2021 @12:07AM (#27102590)
Why is it not ok to convert from a char? Some of the information in the gist is wrong. Type punning with unions for example is legal. ANSI X3.159-1988 is quite clear on that point in its aliasing rules. I've seen a lot of comments people post online saying you must use memcpy to read the bits in a float or that c++ forbids union punning but where is that written. Since if that were true every math library would break.
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