Union type punning in C++

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Undefined behaviour aside is C++ union type punning an acceptable hack or not, given that it is legal in C?
If it works on all the compilers I care about does it really matter that it is *currently* classed as undefined behaviour?
I would say that everyone has "secretly" fucking done it some time or other so the C++ Standards Committee should get there act together and legalize it like it has been in C.
Can anyone provide a straight answer to this?

/Flibble

-- 
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“You won’t burn in hell. But be nice anyway.” – Ricky Gervais

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"Suppose it's all true, and you walk up to the pearly gates, and are confronted by God," Byrne asked on his show The Meaning of Life. "What will Stephen Fry say to him, her, or it?"
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Union type punning in C++ Mr Flibble <flibbleREMOVETHISBIT@i42.co.uk> - 2020-01-01 19:24 +0000
  Re: Union type punning in C++ boltar@nowhere.org - 2020-01-02 09:36 +0000
  Re: Union type punning in C++ Öö Tiib <ootiib@hot.ee> - 2020-01-02 03:34 -0800
    Re: Union type punning in C++ Bo Persson <bo@bo-persson.se> - 2020-01-02 12:49 +0100
      Re: Union type punning in C++ Öö Tiib <ootiib@hot.ee> - 2020-01-02 04:52 -0800
        Re: Union type punning in C++ boltar@nowhere.org - 2020-01-02 17:22 +0000
          Re: Union type punning in C++ Öö Tiib <ootiib@hot.ee> - 2020-01-02 10:26 -0800
            Re: Union type punning in C++ Chris Vine <chris@cvine--nospam--.freeserve.co.uk> - 2020-01-02 21:54 +0000
              Re: Union type punning in C++ boltar@nowhere.org - 2020-01-03 14:49 +0000
                Re: Union type punning in C++ David Brown <david.brown@hesbynett.no> - 2020-01-03 17:11 +0100
                Re: Union type punning in C++ Chris Vine <chris@cvine--nospam--.freeserve.co.uk> - 2020-01-03 17:55 +0000
            Re: Union type punning in C++ boltar@nowhere.org - 2020-01-03 09:55 +0000
              Re: Union type punning in C++ David Brown <david.brown@hesbynett.no> - 2020-01-03 11:20 +0100
              Re: Union type punning in C++ Öö Tiib <ootiib@hot.ee> - 2020-01-03 02:21 -0800
                Re: Union type punning in C++ boltar@nowhere.org - 2020-01-03 14:55 +0000
                Re: Union type punning in C++ Bonita Montero <Bonita.Montero@gmail.com> - 2020-01-03 16:04 +0100
                Re: Union type punning in C++ "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2020-01-03 14:45 -0800
                Re: Union type punning in C++ Bonita Montero <Bonita.Montero@gmail.com> - 2020-01-04 01:26 +0100
                Re: Union type punning in C++ "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2020-01-03 16:55 -0800
                Re: Union type punning in C++ Melzzzzz <Melzzzzz@zzzzz.com> - 2020-01-04 01:02 +0000
                Re: Union type punning in C++ "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2020-01-03 17:06 -0800
                Re: Union type punning in C++ Öö Tiib <ootiib@hot.ee> - 2020-01-03 07:34 -0800
                Re: Union type punning in C++ boltar@nowhere.org - 2020-01-03 16:12 +0000
                Re: Union type punning in C++ Öö Tiib <ootiib@hot.ee> - 2020-01-03 08:49 -0800
                Re: Union type punning in C++ Bonita Montero <Bonita.Montero@gmail.com> - 2020-01-03 19:28 +0100
                Re: Union type punning in C++ Melzzzzz <Melzzzzz@zzzzz.com> - 2020-01-03 18:54 +0000
                Re: Union type punning in C++ Bonita Montero <Bonita.Montero@gmail.com> - 2020-01-04 01:25 +0100
                Re: Union type punning in C++ Melzzzzz <Melzzzzz@zzzzz.com> - 2020-01-04 00:28 +0000
                Re: Union type punning in C++ Bonita Montero <Bonita.Montero@gmail.com> - 2020-01-04 01:41 +0100
                Re: Union type punning in C++ Melzzzzz <Melzzzzz@zzzzz.com> - 2020-01-04 00:52 +0000
                Re: Union type punning in C++ Bonita Montero <Bonita.Montero@gmail.com> - 2020-01-04 08:08 +0100
                Re: Union type punning in C++ Bonita Montero <Bonita.Montero@gmail.com> - 2020-01-04 08:34 +0100
                Re: Union type punning in C++ Bonita Montero <Bonita.Montero@gmail.com> - 2020-01-04 08:43 +0100
                Re: Union type punning in C++ Melzzzzz <Melzzzzz@zzzzz.com> - 2020-01-04 08:20 +0000
                Re: Union type punning in C++ Bonita Montero <Bonita.Montero@gmail.com> - 2020-01-04 09:25 +0100
                Re: Union type punning in C++ Melzzzzz <Melzzzzz@zzzzz.com> - 2020-01-04 08:25 +0000
                Re: Union type punning in C++ Bonita Montero <Bonita.Montero@gmail.com> - 2020-01-04 09:25 +0100
                Re: Union type punning in C++ Melzzzzz <Melzzzzz@zzzzz.com> - 2020-01-04 08:27 +0000
                Re: Union type punning in C++ Bonita Montero <Bonita.Montero@gmail.com> - 2020-01-04 09:36 +0100
                Re: Union type punning in C++ Melzzzzz <Melzzzzz@zzzzz.com> - 2020-01-04 08:41 +0000
                Re: Union type punning in C++ Bonita Montero <Bonita.Montero@gmail.com> - 2020-01-04 09:49 +0100
                Re: Union type punning in C++ Melzzzzz <Melzzzzz@zzzzz.com> - 2020-01-04 09:01 +0000
                Re: Union type punning in C++ Bonita Montero <Bonita.Montero@gmail.com> - 2020-01-04 10:02 +0100
                Re: Union type punning in C++ Melzzzzz <Melzzzzz@zzzzz.com> - 2020-01-04 09:19 +0000
                Re: Union type punning in C++ Bonita Montero <Bonita.Montero@gmail.com> - 2020-01-04 10:38 +0100
                Re: Union type punning in C++ David Brown <david.brown@hesbynett.no> - 2020-01-04 12:45 +0100
                Re: Union type punning in C++ Melzzzzz <Melzzzzz@zzzzz.com> - 2020-01-04 12:00 +0000
                Re: Union type punning in C++ Bonita Montero <Bonita.Montero@gmail.com> - 2020-01-04 13:03 +0100
                Re: Union type punning in C++ Bonita Montero <Bonita.Montero@gmail.com> - 2020-01-04 14:22 +0100
                Re: Union type punning in C++ "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2020-01-03 14:46 -0800
                Re: Union type punning in C++ Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2020-01-03 10:32 -0800
                Re: Union type punning in C++ Öö Tiib <ootiib@hot.ee> - 2020-01-03 10:43 -0800
                Re: Union type punning in C++ Melzzzzz <Melzzzzz@zzzzz.com> - 2020-01-03 18:55 +0000
            Re: Union type punning in C++ Daniel <danielaparker@gmail.com> - 2020-01-08 09:40 -0800
              Re: Union type punning in C++ Öö Tiib <ootiib@hot.ee> - 2020-01-08 13:23 -0800
                Re: Union type punning in C++ Daniel <danielaparker@gmail.com> - 2020-01-08 22:41 -0800
                Re: Union type punning in C++ Daniel <danielaparker@gmail.com> - 2020-01-08 22:52 -0800
                Re: Union type punning in C++ Öö Tiib <ootiib@hot.ee> - 2020-01-09 12:59 -0800
                Re: Union type punning in C++ Daniel <danielaparker@gmail.com> - 2020-01-09 13:32 -0800
                Re: Union type punning in C++ Mister2U@honorific.org - 2020-01-10 12:28 +0000
                Re: Union type punning in C++ David Brown <david.brown@hesbynett.no> - 2020-01-10 14:02 +0100
                Re: Union type punning in C++ Mister2U@honorific.org - 2020-01-10 16:21 +0000
                Re: Union type punning in C++ David Brown <david.brown@hesbynett.no> - 2020-01-10 19:18 +0100
                Re: Union type punning in C++ Daniel <danielaparker@gmail.com> - 2020-01-10 15:41 -0800
                Re: Union type punning in C++ David Brown <david.brown@hesbynett.no> - 2020-01-11 12:01 +0100
                Re: Union type punning in C++ Daniel <danielaparker@gmail.com> - 2020-01-11 07:05 -0800
                Re: Union type punning in C++ David Brown <david.brown@hesbynett.no> - 2020-01-11 23:53 +0100
                Re: Union type punning in C++ Mr Flibble <flibble@i42.removethisbit.co.uk> - 2020-01-12 01:41 +0000
                Re: Union type punning in C++ Daniel <danielaparker@gmail.com> - 2020-01-11 19:00 -0800
                Re: Union type punning in C++ Mr Flibble <flibble@i42.removethisbit.co.uk> - 2020-01-13 17:32 +0000
                Re: Union type punning in C++ Mister2U@honorific.org - 2020-01-11 11:53 +0000
                Re: Union type punning in C++ David Brown <david.brown@hesbynett.no> - 2020-01-11 13:20 +0100
                Re: Union type punning in C++ Mister2U@honorific.org - 2020-01-11 12:33 +0000
                Re: Union type punning in C++ David Brown <david.brown@hesbynett.no> - 2020-01-11 14:28 +0100
                Re: Union type punning in C++ Jorgen Grahn <grahn+nntp@snipabacken.se> - 2020-01-11 10:48 +0000
                Re: Union type punning in C++ Jorgen Grahn <grahn+nntp@snipabacken.se> - 2020-01-11 11:05 +0000
                Re: Union type punning in C++ Mister2U@honorific.org - 2020-01-11 11:55 +0000
          Re: Union type punning in C++ Bo Persson <bo@bo-persson.se> - 2020-01-02 21:12 +0100
            Re: Union type punning in C++ boltar@nowhere.org - 2020-01-03 14:46 +0000
              Re: Union type punning in C++ Bo Persson <bo@bo-persson.se> - 2020-01-03 20:01 +0100
          Re: Union type punning in C++ David Brown <david.brown@hesbynett.no> - 2020-01-02 23:23 +0100
  Re: Union type punning in C++ peter koch <peter.koch.larsen@gmail.com> - 2020-01-02 12:39 -0800
  Re: Union type punning in C++ "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2020-01-02 15:39 -0800
    Re: Union type punning in C++ Öö Tiib <ootiib@hot.ee> - 2020-01-02 16:58 -0800
      Re: Union type punning in C++ "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2020-01-02 17:55 -0800
        Re: Union type punning in C++ Öö Tiib <ootiib@hot.ee> - 2020-01-03 00:40 -0800
          Re: Union type punning in C++ Mr Flibble <flibbleREMOVETHISBIT@i42.co.uk> - 2020-01-03 14:04 +0000
            Re: Union type punning in C++ David Brown <david.brown@hesbynett.no> - 2020-01-03 15:24 +0100
              Re: Union type punning in C++ "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2020-01-03 14:34 -0800
                Re: Union type punning in C++ Melzzzzz <Melzzzzz@zzzzz.com> - 2020-01-03 22:59 +0000
                Re: Union type punning in C++ Mr Flibble <flibbleREMOVETHISBIT@i42.co.uk> - 2020-01-04 00:11 +0000
                Re: Union type punning in C++ Melzzzzz <Melzzzzz@zzzzz.com> - 2020-01-04 00:21 +0000
                Re: Union type punning in C++ Mr Flibble <flibbleREMOVETHISBIT@i42.co.uk> - 2020-01-04 00:26 +0000
                Re: Union type punning in C++ "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2020-01-04 16:51 -0800
                Re: Union type punning in C++ "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2020-01-03 18:47 -0800
                Re: Union type punning in C++ "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2020-01-03 19:07 -0800
            Re: Union type punning in C++ Öö Tiib <ootiib@hot.ee> - 2020-01-03 06:47 -0800
              Re: Union type punning in C++ Mr Flibble <flibbleREMOVETHISBIT@i42.co.uk> - 2020-01-03 14:57 +0000
                Re: Union type punning in C++ Öö Tiib <ootiib@hot.ee> - 2020-01-03 07:38 -0800
                Re: Union type punning in C++ Mr Flibble <flibbleREMOVETHISBIT@i42.co.uk> - 2020-01-03 17:06 +0000
                Re: Union type punning in C++ Öö Tiib <ootiib@hot.ee> - 2020-01-03 11:05 -0800
          Re: Union type punning in C++ "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2020-01-03 14:38 -0800
            Re: Union type punning in C++ Öö Tiib <ootiib@hot.ee> - 2020-01-03 22:37 -0800
      Re: Union type punning in C++ Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-01-11 07:10 -0800
        Re: Union type punning in C++ Öö Tiib <ootiib@hot.ee> - 2020-01-11 10:23 -0800
          Re: Union type punning in C++ Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-01-13 09:01 -0800
            Re: Union type punning in C++ Öö Tiib <ootiib@hot.ee> - 2020-01-13 11:03 -0800
              Re: Union type punning in C++ James Kuyper <jameskuyper@alumni.caltech.edu> - 2020-01-13 12:48 -0800
                Re: Union type punning in C++ Öö Tiib <ootiib@hot.ee> - 2020-01-13 14:15 -0800
                Re: Union type punning in C++ James Kuyper <jameskuyper@alumni.caltech.edu> - 2020-01-13 21:47 -0500
                Re: Union type punning in C++ Öö Tiib <ootiib@hot.ee> - 2020-01-13 23:44 -0800
                Re: Union type punning in C++ James Kuyper <jameskuyper@alumni.caltech.edu> - 2020-01-14 08:26 -0500
              Re: Union type punning in C++ Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-01-14 07:30 -0800
                Re: Union type punning in C++ Öö Tiib <ootiib@hot.ee> - 2020-01-14 09:11 -0800
                Re: Union type punning in C++ James Kuyper <jameskuyper@alumni.caltech.edu> - 2020-01-14 21:52 -0500
                Re: Union type punning in C++ Öö Tiib <ootiib@hot.ee> - 2020-01-14 23:15 -0800
                Re: Union type punning in C++ Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-01-21 02:03 -0800
    Re: Union type punning in C++ Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-01-11 07:28 -0800
      Re: Union type punning in C++ "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2020-01-11 20:40 -0800
        Re: Union type punning in C++ James Kuyper <jameskuyper@alumni.caltech.edu> - 2020-01-12 20:16 -0500
          Re: Union type punning in C++ "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2020-01-12 17:28 -0800
            Re: Union type punning in C++ James Kuyper <jameskuyper@alumni.caltech.edu> - 2020-01-12 21:53 -0500
              Re: Union type punning in C++ Manfred <noname@add.invalid> - 2020-01-13 18:50 +0100
              Re: Union type punning in C++ "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2020-01-13 16:21 -0800
            Re: Union type punning in C++ Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-01-13 08:57 -0800
              Re: Union type punning in C++ "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2020-01-13 16:27 -0800
                Re: Union type punning in C++ Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-01-14 07:05 -0800
                Re: Union type punning in C++ "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2020-01-14 20:58 -0800
                Re: Union type punning in C++ Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-01-21 03:47 -0800
            Re: Union type punning in C++ Öö Tiib <ootiib@hot.ee> - 2020-01-15 01:22 -0800
              Re: Union type punning in C++ James Kuyper <jameskuyper@alumni.caltech.edu> - 2020-01-15 08:04 -0500
                Re: Union type punning in C++ Öö Tiib <ootiib@hot.ee> - 2020-01-15 09:38 -0800
                Re: Union type punning in C++ James Kuyper <jameskuyper@alumni.caltech.edu> - 2020-01-15 11:01 -0800
        Re: Union type punning in C++ Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-01-13 08:37 -0800
          Re: Union type punning in C++ "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2020-01-13 16:29 -0800

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