Re: does char *str="abcd"; alloc addressable memory?

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From	Keith Thompson <Keith.S.Thompson+u@gmail.com>
Newsgroups	comp.lang.c
Subject	Re: does char *str="abcd"; alloc addressable memory?
Date	Sat, 11 Jul 2020 13:39:17 -0700
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James Kuyper <jameskuyper@alumni.caltech.edu> writes:
> On 7/10/20 11:09 PM, John Forkosh wrote:
> ...
>> I seem to recall, from long ago, that it was possible to accidentally
>> (or on purpose, though I don't recall ever seeing/hearing of any good
>> algorithmic reason to) change the value of numeric constants so that
>> afterwards, e.g., i=1;i+=1;(not sure about i++) results in i==3.
>
> What you're describing was certainly true of Fortran, and possibly other
> languages, but C has never worked that way.

I vaguely recall that VAXC, an old compiler for VAX/VMS, allowed
taking the address of a floating-point constant, so that for example
&1.2 would yield a value of type double*.  I have no idea what would
happen if you tried to modify the object via that pointer value.
It was never part of the C language, and I was surprised to see it
(around 1998 or so).  Fortunately we had the newer DECC compiler
as well.

This compiler was so out of date that if you wrote `x=-1`, it would
issue a warning about "-=" being ambiguous and then interpret it
as if you had written `x -= 1`.  The old "-=" syntax for compound
assignment operators is listed as obsolescent in K&R1, 1978.

-- 
Keith Thompson (The_Other_Keith) Keith.S.Thompson+u@gmail.com
Working, but not speaking, for Philips Healthcare
void Void(void) { Void(); } /* The recursive call of the void */

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does char *str="abcd"; alloc addressable memory? John Forkosh <forkosh@panix.com> - 2020-07-06 11:24 +0000
  Re: does char *str="abcd"; alloc addressable memory? jacobnavia <jacob@jacob.remcomp.fr> - 2020-07-06 13:29 +0200
    Mark Twain had something to say about this... (Was: does char *str="abcd"; alloc addressable memory?) gazelle@shell.xmission.com (Kenny McCormack) - 2020-07-06 12:48 +0000
      Re: Mark Twain had something to say about this... (Was: does char *str="abcd"; alloc addressable memory?) BGB <cr88192@gmail.com> - 2020-07-06 11:55 -0500
        Re: Mark Twain had something to say about this... (Was: does char *str="abcd"; alloc addressable memory?) Vir Campestris <vir.campestris@invalid.invalid> - 2020-07-06 21:21 +0100
          Re: Mark Twain had something to say about this... John Forkosh <forkosh@panix.com> - 2020-07-07 03:21 +0000
          Re: Mark Twain had something to say about this... (Was: does char *str="abcd"; alloc addressable memory?) mark.bluemel@gmail.com - 2020-07-09 06:30 -0700
      Re: Mark Twain had something to say about this... (Was: does char *str="abcd"; alloc addressable memory?) Richard Damon <Richard@Damon-Family.org> - 2020-07-06 22:16 -0400
        Re: Mark Twain had something to say about this... Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2020-07-06 23:22 -0700
      Re: Mark Twain had something to say about this... John Forkosh <forkosh@panix.com> - 2020-07-07 02:46 +0000
      Re: Mark Twain had something to say about this... (Was: does char *str="abcd"; alloc addressable memory?) jacobnavia <jacob@jacob.remcomp.fr> - 2020-07-07 09:29 +0200
    Re: does char *str="abcd"; alloc addressable memory? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2020-07-06 11:25 -0700
      Re: does char *str="abcd"; alloc addressable memory? John Forkosh <forkosh@panix.com> - 2020-07-07 03:05 +0000
        Re: does char *str="abcd"; alloc addressable memory? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2020-07-06 23:25 -0700
          Re: does char *str="abcd"; alloc addressable memory? John Forkosh <forkosh@panix.com> - 2020-07-07 06:47 +0000
            Re: does char *str="abcd"; alloc addressable memory? John Forkosh <forkosh@panix.com> - 2020-07-07 07:00 +0000
              Re: does char *str="abcd"; alloc addressable memory? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2020-07-07 01:24 -0700
              Re: does char *str="abcd"; alloc addressable memory? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-07-07 20:47 +0100
                Re: does char *str="abcd"; alloc addressable memory? John Forkosh <forkosh@panix.com> - 2020-07-08 03:43 +0000
        Re: does char *str="abcd"; alloc addressable memory? David Brown <david.brown@hesbynett.no> - 2020-07-07 09:35 +0200
          Re: does char *str="abcd"; alloc addressable memory? John Forkosh <forkosh@panix.com> - 2020-07-07 07:54 +0000
            Re: does char *str="abcd"; alloc addressable memory? David Brown <david.brown@hesbynett.no> - 2020-07-07 11:27 +0200
          Re: does char *str="abcd"; alloc addressable memory? Richard Damon <Richard@Damon-Family.org> - 2020-07-09 06:53 -0400
            Re: does char *str="abcd"; alloc addressable memory? David Brown <david.brown@hesbynett.no> - 2020-07-09 14:48 +0200
              Re: does char *str="abcd"; alloc addressable memory? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-07-09 17:01 +0100
                Re: does char *str="abcd"; alloc addressable memory? David Brown <david.brown@hesbynett.no> - 2020-07-09 22:10 +0200
                Re: does char *str="abcd"; alloc addressable memory? scott@slp53.sl.home (Scott Lurndal) - 2020-07-09 20:23 +0000
                Re: does char *str="abcd"; alloc addressable memory? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-07-09 23:56 +0100
                Re: does char *str="abcd"; alloc addressable memory? antispam@math.uni.wroc.pl - 2020-07-10 03:25 +0000
                Re: does char *str="abcd"; alloc addressable memory? Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2020-07-10 11:56 -0400
                Re: does char *str="abcd"; alloc addressable memory? richard@cogsci.ed.ac.uk (Richard Tobin) - 2020-07-10 12:31 +0000
                Re: does char *str="abcd"; alloc addressable memory? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2020-07-09 13:35 -0700
                Re: does char *str="abcd"; alloc addressable memory? scott@slp53.sl.home (Scott Lurndal) - 2020-07-09 22:17 +0000
                Re: does char *str="abcd"; alloc addressable memory? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-07-09 23:50 +0100
            Re: does char *str="abcd"; alloc addressable memory? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-07-09 16:52 +0100
            Re: does char *str="abcd"; alloc addressable memory? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-07-09 10:13 -0700
              Re: does char *str="abcd"; alloc addressable memory? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2020-07-09 11:24 -0700
                Re: does char *str="abcd"; alloc addressable memory? John Forkosh <forkosh@panix.com> - 2020-07-09 22:59 +0000
                Re: does char *str="abcd"; alloc addressable memory? Manfred <noname@add.invalid> - 2020-07-10 16:36 +0200
                Re: does char *str="abcd"; alloc addressable memory? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-07-10 15:54 +0100
                Re: does char *str="abcd"; alloc addressable memory? Manfred <noname@add.invalid> - 2020-07-10 18:33 +0200
                Re: does char *str="abcd"; alloc addressable memory? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-07-10 22:50 +0100
                Re: does char *str="abcd"; alloc addressable memory? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-07-11 16:21 +0100
                Re: does char *str="abcd"; alloc addressable memory? Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2020-07-11 08:55 -0700
                Re: does char *str="abcd"; alloc addressable memory? Bart <bc@freeuk.com> - 2020-07-11 17:09 +0100
                Re: does char *str="abcd"; alloc addressable memory? Manfred <noname@add.invalid> - 2020-07-11 18:34 +0200
                Re: does char *str="abcd"; alloc addressable memory? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2020-07-10 13:17 -0700
                Re: does char *str="abcd"; alloc addressable memory? Manfred <noname@add.invalid> - 2020-07-11 02:00 +0200
                Re: does char *str="abcd"; alloc addressable memory? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2020-07-10 17:46 -0700
                Re: does char *str="abcd"; alloc addressable memory? John Forkosh <forkosh@panix.com> - 2020-07-11 03:09 +0000
                Re: does char *str="abcd"; alloc addressable memory? Manfred <noname@add.invalid> - 2020-07-11 18:43 +0200
                Re: does char *str="abcd"; alloc addressable memory? James Kuyper <jameskuyper@alumni.caltech.edu> - 2020-07-11 15:09 -0400
                Re: does char *str="abcd"; alloc addressable memory? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2020-07-11 13:39 -0700
                Re: does char *str="abcd"; alloc addressable memory? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2020-07-11 15:50 -0700
                Re: does char *str="abcd"; alloc addressable memory? John Forkosh <forkosh@panix.com> - 2020-07-12 01:06 +0000
                Re: does char *str="abcd"; alloc addressable memory? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-07-10 08:54 -0700
                Re: does char *str="abcd"; alloc addressable memory? John Forkosh <forkosh@panix.com> - 2020-07-11 03:26 +0000
                Re: does char *str="abcd"; alloc addressable memory? Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2020-07-11 03:56 -0700
                Re: does char *str="abcd"; alloc addressable memory? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-07-10 08:46 -0700
                Re: does char *str="abcd"; alloc addressable memory? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2020-07-10 13:38 -0700
                Re: does char *str="abcd"; alloc addressable memory? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2020-07-10 13:54 -0700
        Re: does char *str="abcd"; alloc addressable memory? James Kuyper <jameskuyper@alumni.caltech.edu> - 2020-07-07 08:52 -0400
    Re: does char *str="abcd"; alloc addressable memory? John Forkosh <forkosh@panix.com> - 2020-07-07 02:56 +0000
      Re: does char *str="abcd"; alloc addressable memory? antispam@math.uni.wroc.pl - 2020-07-07 19:08 +0000
        Re: does char *str="abcd"; alloc addressable memory? John Forkosh <forkosh@panix.com> - 2020-07-08 04:07 +0000
          Re: does char *str="abcd"; alloc addressable memory? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2020-07-07 21:54 -0700
  Re: does char *str="abcd"; alloc addressable memory? Ike Naar <ike@sdf.org> - 2020-07-06 11:56 +0000
  Re: does char *str="abcd"; alloc addressable memory? Bonita Montero <Bonita.Montero@gmail.com> - 2020-07-06 13:57 +0200
    Re: does char *str="abcd"; alloc addressable memory? Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2020-07-06 05:37 -0700
      Re: does char *str="abcd"; alloc addressable memory? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-07-06 19:52 +0100
        Re: does char *str="abcd"; alloc addressable memory? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2020-07-06 12:20 -0700
      Re: does char *str="abcd"; alloc addressable memory? John Forkosh <forkosh@panix.com> - 2020-07-07 03:32 +0000
        Re: does char *str="abcd"; alloc addressable memory? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-07-07 06:26 -0700
          Re: does char *str="abcd"; alloc addressable memory? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2020-07-07 10:03 -0700
            Re: does char *str="abcd"; alloc addressable memory? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2020-07-09 10:07 -0700
          Re: does char *str="abcd"; alloc addressable memory? John Forkosh <forkosh@panix.com> - 2020-07-08 03:57 +0000
            Re: does char *str="abcd"; alloc addressable memory? James Kuyper <jameskuyper@alumni.caltech.edu> - 2020-07-08 11:02 -0400
    Re: does char *str="abcd"; alloc addressable memory? James Kuyper <jameskuyper@alumni.caltech.edu> - 2020-07-06 09:43 -0700
      Re: does char *str="abcd"; alloc addressable memory? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2020-07-06 19:35 +0100
    Re: does char *str="abcd"; alloc addressable memory? Andrey Tarasevich <andreytarasevich@hotmail.com> - 2020-07-06 18:50 -0700
  Re: does char *str="abcd"; alloc addressable memory? James Kuyper <jameskuyper@alumni.caltech.edu> - 2020-07-06 08:35 -0400
    Re: does char *str="abcd"; alloc addressable memory? James Kuyper <jameskuyper@alumni.caltech.edu> - 2020-07-06 11:21 -0400
  Re: does char *str="abcd"; alloc addressable memory? Barry Schwarz <schwarzb@delq.com> - 2020-07-06 09:58 -0700
    Re: does char *str="abcd"; alloc addressable memory? scott@slp53.sl.home (Scott Lurndal) - 2020-07-06 23:07 +0000
      Re: does char *str="abcd"; alloc addressable memory? Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2020-07-06 20:03 -0400
        Re: does char *str="abcd"; alloc addressable memory? scott@slp53.sl.home (Scott Lurndal) - 2020-07-07 14:36 +0000
          Re: does char *str="abcd"; alloc addressable memory? Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2020-07-07 11:58 -0400

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