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Re: double strtod( const char *nPtr, char **endPrt);

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On 11/12/2015 6:15 PM, glen herrmannsfeldt wrote:
> Keith Thompson <kst-u@mib.org> wrote:
>> supercat@casperkitty.com writes:
> (snip)
>>> While I don't think anything would forbid an implementation where string
>>> literals could create objects at run time, I would suggest that they more
>>> often create objects at compile time which are aggregated into an object
>>> which gets created at load time.  String literal expressions then identify
>>> pieces of that object.
>
>> Objects don't exist at compile time.
>
> I suspect it isn't part of the C standard, but most systems create
> static objects at compile time. They exist in the object module,
> and resultant load module.

     I think Keith's point is that the contents of the "object module"
and "load module" are not objects until run time; they're just
instructions to the starter-upper to create some objects before
calling main().

>> A compiler doesn't create an object.  It generates code that results in
>> the creation of an object when that code is executed.
>
> C conveniently makes it hard to create large static objects initialized
> to other than zero. Many object module and load module forms have
> optmizations for static zero, but not all.

     ... which seems to support Keith's view.  You write source code
for a big zero object like `static char array[10000];', but you may
search in vain for a 10000-byte thingumabob in the products of the
compiler and linker.  There's a good chance you'll just find a little
notation somewhere that says "Dear run-time: Please set aside 42KB of
pre-zeroed bytes (maybe called bss), and I'll treat bytes X through
X+9999 of that region as `array'." If that sort of thing happens, it's
pretty clear that the object has not been created prior to run-time.

-- 
esosman@comcast-dot-net.invalid
"Don't be afraid of work. Make work afraid of you." -- TLM

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double strtod( const char *nPtr, char **endPrt); G G <gdotone@gmail.com> - 2015-11-11 22:55 -0800
  Re: double strtod( const char *nPtr, char **endPrt); Richard Heathfield <rjh@cpax.org.uk> - 2015-11-12 07:24 +0000
    Re: double strtod( const char *nPtr, char **endPrt); G G <gdotone@gmail.com> - 2015-11-11 23:42 -0800
  Re: double strtod( const char *nPtr, char **endPrt); Keith Thompson <kst-u@mib.org> - 2015-11-12 08:31 -0800
    Re: double strtod( const char *nPtr, char **endPrt); supercat@casperkitty.com - 2015-11-12 08:52 -0800
    Re: double strtod( const char *nPtr, char **endPrt); G G <gdotone@gmail.com> - 2015-11-12 09:43 -0800
      Re: double strtod( const char *nPtr, char **endPrt); Richard Heathfield <rjh@cpax.org.uk> - 2015-11-12 17:59 +0000
      Re: double strtod( const char *nPtr, char **endPrt); Eric Sosman <esosman@comcast-dot-net.invalid> - 2015-11-12 13:10 -0500
      Re: double strtod( const char *nPtr, char **endPrt); James Kuyper <jameskuyper@verizon.net> - 2015-11-12 13:19 -0500
      Re: double strtod( const char *nPtr, char **endPrt); Keith Thompson <kst-u@mib.org> - 2015-11-12 11:32 -0800
        Re: double strtod( const char *nPtr, char **endPrt); supercat@casperkitty.com - 2015-11-12 12:17 -0800
          Re: double strtod( const char *nPtr, char **endPrt); Keith Thompson <kst-u@mib.org> - 2015-11-12 12:48 -0800
            Re: double strtod( const char *nPtr, char **endPrt); supercat@casperkitty.com - 2015-11-12 13:39 -0800
              Re: double strtod( const char *nPtr, char **endPrt); glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2015-11-12 23:24 +0000
              Re: double strtod( const char *nPtr, char **endPrt); Keith Thompson <kst-u@mib.org> - 2015-11-12 17:14 -0800
                Re: double strtod( const char *nPtr, char **endPrt); supercat@casperkitty.com - 2015-11-12 17:42 -0800
                Re: double strtod( const char *nPtr, char **endPrt); Keith Thompson <kst-u@mib.org> - 2015-11-12 18:20 -0800
            Re: double strtod( const char *nPtr, char **endPrt); glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2015-11-12 23:15 +0000
              Re: double strtod( const char *nPtr, char **endPrt); Eric Sosman <esosman@comcast-dot-net.invalid> - 2015-11-12 18:30 -0500
                Re: double strtod( const char *nPtr, char **endPrt); supercat@casperkitty.com - 2015-11-12 16:47 -0800
                Re: double strtod( const char *nPtr, char **endPrt); Keith Thompson <kst-u@mib.org> - 2015-11-12 18:07 -0800
                Re: double strtod( const char *nPtr, char **endPrt); glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2015-11-13 02:41 +0000
                Re: double strtod( const char *nPtr, char **endPrt); glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2015-11-13 02:53 +0000
        Re: double strtod( const char *nPtr, char **endPrt); G G <gdotone@gmail.com> - 2015-11-12 12:17 -0800
  Re: double strtod( const char *nPtr, char **endPrt); Malcolm McLean <malcolm.mclean5@btinternet.com> - 2015-11-12 12:34 -0800
    Re: double strtod( const char *nPtr, char **endPrt); Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-11-12 23:54 +0000
      Re: double strtod( const char *nPtr, char **endPrt); Malcolm McLean <malcolm.mclean5@btinternet.com> - 2015-11-12 16:23 -0800
        Re: double strtod( const char *nPtr, char **endPrt); Ian Collins <ian-news@hotmail.com> - 2015-11-13 14:09 +1300
          Re: double strtod( const char *nPtr, char **endPrt); Malcolm McLean <malcolm.mclean5@btinternet.com> - 2015-11-12 17:31 -0800
            Re: double strtod( const char *nPtr, char **endPrt); Ian Collins <ian-news@hotmail.com> - 2015-11-13 14:46 +1300
        Re: double strtod( const char *nPtr, char **endPrt); Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-11-13 02:07 +0000
        Re: double strtod( const char *nPtr, char **endPrt); David Brown <david.brown@hesbynett.no> - 2015-11-13 08:48 +0100
    Re: double strtod( const char *nPtr, char **endPrt); Keith Thompson <kst-u@mib.org> - 2015-11-12 16:57 -0800

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