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Re: return -1 using size_t???

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On 2012-02-13, Ben Bacarisse <ben.usenet@bsb.me.uk> wrote:
> Do you know what happened when exponent bits got set (and indeed
> if they could get set) by operations like ~?

Setting exponent bits was not a problem in itself.
The trouble came when the result was to be interpreted as an integer.
The compiler would then insert normalize-to-integer (NTGR) instructions
in strategic places.
This instruction trapped if normalization was not possible.

Of course, in some cases, even after setting exponent bits, the
resulting value could still be normalizable to a valid integer;
e.g. starting with integer value 77 (mantissa=77, exponent=0), setting
exponent bits so that the exponent becomes 3 yields the new value
77*8**3 = 39424, which is normalized to (mantissa=39424, exponent=0).

The system's main programming language was an extended dialect of Algol.
In that language, it was more convenient to use REAL or BOOLEAN
variables (both 48 bits wide) for bit operations, as these types were
not subject to integer normalization.

I'm not sure if there even was a C compiler available at the time.

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return -1 using size_t??? Robert Hayes <rhyes80@gmail.com> - 2012-02-11 11:21 -0800
  Re: return -1 using size_t??? Shao Miller <sha0.miller@gmail.com> - 2012-02-11 15:00 -0500
    Re: return -1 using size_t??? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-02-11 23:24 +0000
  Re: return -1 using size_t??? Jeffrey R <joeff@nospam.com> - 2012-02-11 19:58 +0000
    Re: return -1 using size_t??? Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-02-11 15:11 -0500
  Re: return -1 using size_t??? Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-02-11 15:07 -0500
    Re: return -1 using size_t??? Robert Hayes <rhyes80@gmail.com> - 2012-02-11 12:42 -0800
      Re: return -1 using size_t??? Malcolm McLean <malcolm.mclean5@btinternet.com> - 2012-02-11 13:19 -0800
        Re: return -1 using size_t??? Keith Thompson <kst-u@mib.org> - 2012-02-11 17:10 -0800
          Re: return -1 using size_t??? Malcolm McLean <malcolm.mclean5@btinternet.com> - 2012-02-12 03:48 -0800
            Re: return -1 using size_t??? Keith Thompson <kst-u@mib.org> - 2012-02-12 04:04 -0800
      Re: return -1 using size_t??? Jeffrey R <joeff@nospam.com> - 2012-02-11 22:25 +0000
        Re: return -1 using size_t??? Devil with the China Blue Dress <chine.bleu@yahoo.com> - 2012-02-11 14:36 -0800
          Re: return -1 using size_t??? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-02-11 23:17 +0000
        Re: return -1 using size_t??? Jeroen Mostert <jmostert@xs4all.nl> - 2012-02-11 23:46 +0100
          Re: return -1 using size_t??? pete <pfiland@mindspring.com> - 2012-02-11 19:18 -0500
        Re: return -1 using size_t??? Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-02-12 08:38 -0500
      Re: return -1 using size_t??? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-02-11 23:32 +0000
      Re: return -1 using size_t??? pete <pfiland@mindspring.com> - 2012-02-11 19:15 -0500
    Re: return -1 using size_t??? Ralph Spitzner <rasp@spitzner.org> - 2012-02-13 13:51 +0100
  Re: return -1 using size_t??? Devil with the China Blue Dress <chine.bleu@yahoo.com> - 2012-02-11 12:40 -0800
    Re: return -1 using size_t??? Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-02-11 17:02 -0500
      Re: return -1 using size_t??? Devil with the China Blue Dress <chine.bleu@yahoo.com> - 2012-02-11 14:11 -0800
        Re: return -1 using size_t??? Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-02-11 17:21 -0500
          Re: return -1 using size_t??? Devil with the China Blue Dress <chine.bleu@yahoo.com> - 2012-02-11 14:31 -0800
            Re: return -1 using size_t??? Willem <willem@toad.stack.nl> - 2012-02-11 22:52 +0000
            Re: return -1 using size_t??? Jens Gustedt <jens.gustedt@loria.fr> - 2012-02-12 00:20 +0100
              Re: return -1 using size_t??? Devil with the China Blue Dress <chine.bleu@yahoo.com> - 2012-02-12 09:21 -0800
                Re: return -1 using size_t??? Keith Thompson <kst-u@mib.org> - 2012-02-12 12:27 -0800
                Re: return -1 using size_t??? Jeroen Mostert <jmostert@xs4all.nl> - 2012-02-12 22:17 +0100
                Re: return -1 using size_t??? Devil with the China Blue Dress <chine.bleu@yahoo.com> - 2012-02-12 15:10 -0800
                Re: return -1 using size_t??? Nick Keighley <nick_keighley_nospam@hotmail.com> - 2012-02-13 03:11 -0800
                Re: return -1 using size_t??? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-02-12 23:25 +0000
                Re: return -1 using size_t??? Jeroen Mostert <jmostert@xs4all.nl> - 2012-02-13 07:46 +0100
                Re: return -1 using size_t??? Ike Naar <ike@sverige.freeshell.org> - 2012-02-13 10:27 +0000
                Re: return -1 using size_t??? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-02-13 12:36 +0000
                Re: return -1 using size_t??? Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2012-02-13 10:26 -0700
                Re: return -1 using size_t??? Ike Naar <ike@iceland.freeshell.org> - 2012-02-14 00:18 +0000
                Re: return -1 using size_t??? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-02-14 00:29 +0000
                Re: return -1 using size_t??? Devil with the China Blue Dress <chine.bleu@yahoo.com> - 2012-02-13 16:37 -0800
                Re: return -1 using size_t??? Angel <angel+news@spamcop.net> - 2012-02-13 11:47 +0000
                Re: return -1 using size_t??? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-02-13 12:54 +0000
                Re: return -1 using size_t??? Angel <angel+news@spamcop.net> - 2012-02-13 14:30 +0000
                Re: return -1 using size_t??? Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2012-02-22 01:53 +0200
                Re: return -1 using size_t??? James Kuyper <jameskuyper@verizon.net> - 2012-02-13 12:11 -0500
                Re: return -1 using size_t??? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-02-13 17:28 +0000
                Re: return -1 using size_t??? James Kuyper <jameskuyper@verizon.net> - 2012-02-13 13:08 -0500
                Re: return -1 using size_t??? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-02-13 23:06 +0000
                Re: return -1 using size_t??? William Ahern <william@wilbur.25thandClement.com> - 2012-02-13 14:39 -0800
                Re: return -1 using size_t??? Keith Thompson <kst-u@mib.org> - 2012-02-13 14:59 -0800
                Re: return -1 using size_t??? Jens Gustedt <jens.gustedt@loria.fr> - 2012-02-12 22:17 +0100
                Re: return -1 using size_t??? Devil with the China Blue Dress <chine.bleu@yahoo.com> - 2012-02-12 15:06 -0800
                Re: return -1 using size_t??? Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-02-12 18:12 -0500
                Re: return -1 using size_t??? Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2012-02-22 02:15 +0200
  Re: return -1 using size_t??? Barry Schwarz <schwarzb@dqel.com> - 2012-02-11 14:27 -0800
    Re: return -1 using size_t??? Keith Thompson <kst-u@mib.org> - 2012-02-11 17:34 -0800

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