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Re: Initialization Of Static Pointer Variables

From "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com>
Newsgroups comp.lang.c
Subject Re: Initialization Of Static Pointer Variables
Date 2026-08-21 12:12 -0700
Organization A noiseless patient Spider
Message-ID <116a7vj$iojj$1@dont-email.me> (permalink)
References <11681np$3s8jk$4@dont-email.me> <11683d0$jki7$1@artemis.inf.ed.ac.uk>

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On 8/20/2026 4:42 PM, Richard Tobin wrote:
> In article <11681np$3s8jk$4@dont-email.me>,
> Lawrence D;Oliveiro  <ldo@nz.invalid> wrote:
> 
>> The spec also says that all static variables are initialized to zero
>> at program start time. Are pointer variables allowed to be given an
>> all-zero bit pattern at this time? Or are they supposed to be
>> initialized to the NULL value (if that's different) instead?
> 
> ISO C 1999, 6.7.8:
> 
> If an object that has automatic storage duration is not initialized
> explicitly, its value is indeterminate. If an object that has static
> storage duration is not initialized explicitly, then:
> 
> — if it has pointer type, it is initialized to a null pointer;

Oh. I must have missed that one.

so:

static void* g_ptr;


is guaranteed to be nullptr? Just to clarify...


> 
> — if it has arithmetic type, it is initialized to (positive or
> unsigned) zero;
> 
> — if it is an aggregate, every member is initialized (recursively)
> according to these rules;
> 
> — if it is a union, the first named member is initialized
> (recursively) according to these rules


[...]

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Initialization Of Static Pointer Variables Lawrence D’Oliveiro <ldo@nz.invalid> - 2026-08-20 23:14 +0000
  Re: Initialization Of Static Pointer Variables "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2026-08-20 16:28 -0700
    Re: Initialization Of Static Pointer Variables "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2026-08-20 16:29 -0700
  Re: Initialization Of Static Pointer Variables richard@cogsci.ed.ac.uk (Richard Tobin) - 2026-08-20 23:42 +0000
    Re: Initialization Of Static Pointer Variables "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2026-08-21 12:12 -0700
      Re: Initialization Of Static Pointer Variables David Brown <david.brown@hesbynett.no> - 2026-08-22 13:12 +0200
        Re: Initialization Of Static Pointer Variables steve g <Sgonedes1977@gmail.com> - 2026-08-23 16:01 -0400
          Re: Initialization Of Static Pointer Variables Lawrence D’Oliveiro <ldo@nz.invalid> - 2026-08-23 22:16 +0000
          Re: Initialization Of Static Pointer Variables Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-08-23 15:29 -0700
            Re: Initialization Of Static Pointer Variables David Brown <david.brown@hesbynett.no> - 2026-08-24 10:16 +0200
              Re: Initialization Of Static Pointer Variables Richard Harnden <richard.nospam@gmail.invalid> - 2026-08-24 09:45 +0100
                Re: Initialization Of Static Pointer Variables Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-08-24 03:04 -0700
                Re: Initialization Of Static Pointer Variables David Brown <david.brown@hesbynett.no> - 2026-08-24 12:40 +0200
                Re: Initialization Of Static Pointer Variables Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-08-24 13:16 -0700
          Re: Initialization Of Static Pointer Variables richard@cogsci.ed.ac.uk (Richard Tobin) - 2026-08-23 22:28 +0000
          Cryptographic zero initialization (was: Re: Initialization Of Static Pointer Variables) Johann 'Myrkraverk' Oskarsson <johann@myrkraverk.invalid> - 2026-08-24 19:26 +0800
  Re: Initialization Of Static Pointer Variables Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-08-20 16:52 -0700
  Re: Initialization Of Static Pointer Variables James Kuyper <jameskuyper@alumni.caltech.edu> - 2026-08-20 20:12 -0400
  Re: Initialization Of Static Pointer Variables bart <bc@freeuk.com> - 2026-08-21 01:16 +0100
    Re: Initialization Of Static Pointer Variables Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2026-08-20 17:53 -0700
    Re: Initialization Of Static Pointer Variables James Kuyper <jameskuyper@alumni.caltech.edu> - 2026-08-20 23:01 -0400
      Re: Initialization Of Static Pointer Variables Lawrence D’Oliveiro <ldo@nz.invalid> - 2026-08-21 08:02 +0000
        Re: Initialization Of Static Pointer Variables scott@slp53.sl.home (Scott Lurndal) - 2026-08-21 14:53 +0000
          Re: Initialization Of Static Pointer Variables richard@cogsci.ed.ac.uk (Richard Tobin) - 2026-08-21 15:28 +0000
    Re: Initialization Of Static Pointer Variables David Brown <david.brown@hesbynett.no> - 2026-08-21 09:12 +0200
  Re: Initialization Of Static Pointer Variables David Brown <david.brown@hesbynett.no> - 2026-08-21 09:03 +0200
    Re: Initialization Of Static Pointer Variables Johann 'Myrkraverk' Oskarsson <johann@myrkraverk.invalid> - 2026-08-21 17:54 +0800
  Re: Initialization Of Static Pointer Variables Johann 'Myrkraverk' Oskarsson <johann@myrkraverk.invalid> - 2026-08-21 17:50 +0800
  Re: Initialization Of Static Pointer Variables Tim Rentsch <tr.17687@z991.linuxsc.com> - 2026-08-21 06:02 -0700

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