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From: Tim Rentsch <tr.17687@z991.linuxsc.com>
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Subject: Re: Don't be fooled by cpp.sh
Date: Fri, 10 Jan 2020 21:12:57 -0800
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James Kuyper <jameskuyper@alumni.caltech.edu> writes:

> Also, don't you find it a bit odd that what you consider to be
> "the whole point of a union" has always had undefined behavior in
> C++, and had undefined behavior in C all the way up until C2011?

Note that James's opinion on when the behavior was defined in C
doesn't match the C standard committee's opinion on when the
behavior was defined in C.  See for example DR 283 (dated 2002)

    http://www.open-std.org/jtc1/sc22/wg14/www/docs/dr_283.htm

> It wasn't until C2011 that a footnote was added to the C standard
> identifying that the behavior of "write as one type and read as
> another" is to reinterpret the associated memory as having the
> type of the lvalue used to read it.

False.  See N1256 if you don't believe me.