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Re: N3242 8.5.1/15 -- braced union declarations limited only to first member

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On Saturday, 20 September 2014 07:40:02 UTC+1, Rick C. Hodgin  wrote:
> Should have been:
> -----
> I would like the compiler to determine the union member by its type
> when possible.
>
> struct SExample
> {
>     union {
>         int i;
>         float f;
>     };
> };
>
> SExample myArray[] =
> {
>     { 10 }, // Initialized to i member as int
>     { 3.14f } // Initialized to f member as float
> };
>
> Also, on conflicting types, such as 5 for int and
> char, if the bytes they occupy would all map to
> the same location in the union, the cast would
> not be required.

That would be a terrible idea!  It means that code would
compile on a little-endian machine, but not a big-endian one.
(For example)


I agree that C99 designated initializers would be a much
better solution:
- They have already been cast into standardese.
- If gcc doesn't support them for C++, it's probably not hard to
  make it do so (so we can gain implementation experience).
- They would be of more general utility than just initializing
  unions.


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N3242 8.5.1/15 -- braced union declarations limited only to first member rick.c.hodgin@googlemail.com - 2014-08-30 13:29 -0600
  Re: N3242 8.5.1/15 -- braced union declarations limited only to first member "Rick C. Hodgin" <rick.c.hodgin@googlemail.com> - 2014-09-16 21:01 -0600
    Re: N3242 8.5.1/15 -- braced union declarations limited only to first member Philip Guenther <guenther@googlemail.com> - 2014-09-17 19:29 -0600
      Re: N3242 8.5.1/15 -- braced union declarations limited only to first member "Rick C. Hodgin" <rick.c.hodgin@googlemail.com> - 2014-09-19 01:06 -0600
        Re: N3242 8.5.1/15 -- braced union declarations limited only to first member "Rick C. Hodgin" <rick.c.hodgin@googlemail.com> - 2014-09-20 01:37 -0600
          Re: N3242 8.5.1/15 -- braced union declarations limited only to first member Martin Bonner <martinfrompi@yahoo.co.uk> - 2014-09-23 14:52 -0600
            Re: N3242 8.5.1/15 -- braced union declarations limited only to first member "Rick C. Hodgin" <rick.c.hodgin@googlemail.com> - 2014-09-24 16:30 -0600
      Re: N3242 8.5.1/15 -- braced union declarations limited only to first  member James Kuyper <jameskuyper@verizon.net> - 2014-09-19 01:06 -0600
      Re: N3242 8.5.1/15 -- braced union declarations limited only to first member Francis Glassborow <Francis.glassborow@btinternet.com> - 2014-09-19 01:06 -0600

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