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Groups > comp.lang.c > #11368

Re: initialization of local static variable

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Le 08/10/11 01:25, China Blue Corn Chips a écrit :
> In article<j6nkfh$3tt$1@speranza.aioe.org>, jacob navia<jacob@spamsink.net>
> wrote:
>>
>> Well, why shouldn't be possible?
>>
>> I don't see any reason. The compiler can do it, the language
>> looks the same, why shouldn't I do it?
>>
>> Besides the obvious (the standard doesn't like it) is there
>> any reason not to do it?
>
> What does it mean? Does it mean initalise the static exactly once before the
> first dynamic reference?

no

> Or does it mean initialise on every call?

Yes, as I have it now.

> If the
> latter, what does that do to auto-initialising function that require a flag be
> initialised once (static bool firstcall = true)?
>

That is an initialization with a compile time constant and the old
rules apply.

> Allowing only initialise at load to a constant simplifies the loader and
> provides enough power to implement the other kinds of initialisation.
>
> #define once(statement) do { \
>          static bool onceflag = true; \
>          if (onceflag) {onceflag = false; {statement;}} \
> } while(0)
>

This remains valid

> #define reinitialiseEachCall(variable,value) variable; variable=(value)
>

That also :-)

> static int perfect = 6; /*simple constant initialisation*/
> static double pi; once(pi = 2*atan(1));
> static int reinitialiseEachCall(b, a);
>

That will not work at the top level (global)

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initialization of local static variable "V.Subramanian, India" <subramanian100in@yahoo.com> - 2011-10-06 23:33 -0700
  Re: initialization of local static variable pete <pfiland@mindspring.com> - 2011-10-07 02:51 -0400
  Re: initialization of local static variable "BartC" <bc@freeuk.com> - 2011-10-07 10:44 +0100
  Re: initialization of local static variable China Blue Corn Chips <chine.bleu@yahoo.com> - 2011-10-07 03:03 -0700
    Re: initialization of local static variable "BartC" <bc@freeuk.com> - 2011-10-07 11:33 +0100
      Re: initialization of local static variable jt@toerring.de (Jens Thoms Toerring) - 2011-10-07 11:11 +0000
        Re: initialization of local static variable "BartC" <bc@freeuk.com> - 2011-10-07 12:51 +0100
          Re: initialization of local static variable jt@toerring.de (Jens Thoms Toerring) - 2011-10-07 15:56 +0000
            Re: initialization of local static variable Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-10-07 20:29 +0100
              Re: initialization of local static variable jacob navia <jacob@spamsink.net> - 2011-10-07 21:38 +0200
                Re: initialization of local static variable Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-10-07 21:16 +0100
                Re: initialization of local static variable jacob navia <jacob@spamsink.net> - 2011-10-07 22:22 +0200
                Re: initialization of local static variable jt@toerring.de (Jens Thoms Toerring) - 2011-10-07 22:25 +0000
                Re: initialization of local static variable jacob navia <jacob@spamsink.net> - 2011-10-08 00:40 +0200
                Re: initialization of local static variable Ian Collins <ian-news@hotmail.com> - 2011-10-08 11:56 +1300
                Re: initialization of local static variable jacob navia <jacob@spamsink.net> - 2011-10-08 01:53 +0200
                Re: initialization of local static variable Jens Gustedt <jens.gustedt@loria.fr> - 2011-10-09 23:04 +0200
                Re: initialization of local static variable Andrew Haley <andrew29@littlepinkcloud.invalid> - 2011-10-10 11:54 -0500
                Re: initialization of local static variable Ike Naar <ike@sverige.freeshell.org> - 2011-10-10 17:41 +0000
                Re: initialization of local static variable Andrew Haley <andrew29@littlepinkcloud.invalid> - 2011-10-10 17:35 -0500
                Re: initialization of local static variable jt@toerring.de (Jens Thoms Toerring) - 2011-10-08 00:02 +0000
                Re: initialization of local static variable "BartC" <bc@freeuk.com> - 2011-10-08 01:26 +0100
                Re: initialization of local static variable "Philip Lantz" <prl@canterey.us> - 2011-10-08 03:01 -0700
                Re: initialization of local static variable "BartC" <bc@freeuk.com> - 2011-10-07 21:42 +0100
                Re: initialization of local static variable China Blue Corn Chips <chine.bleu@yahoo.com> - 2011-10-07 16:25 -0700
                Re: initialization of local static variable jacob navia <jacob@spamsink.net> - 2011-10-08 01:51 +0200
                Re: initialization of local static variable China Blue Corn Chips <chine.bleu@yahoo.com> - 2011-10-07 18:21 -0700
                Re: initialization of local static variable Nobody <nobody@nowhere.com> - 2011-10-08 15:36 +0100
                Re: initialization of local static variable Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-10-08 22:06 +0100
                Re: initialization of local static variable Nobody <nobody@nowhere.com> - 2011-10-09 05:35 +0100
                Re: initialization of local static variable Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-10-09 09:25 +0100
                Re: initialization of local static variable "io_x" <a@b.c.invalid> - 2011-10-09 11:00 +0200
                Re: initialization of local static variable Barry Schwarz <schwarzb@dqel.com> - 2011-10-09 10:56 -0700
                Re: initialization of local static variable James Kuyper <jameskuyper@verizon.net> - 2011-10-09 14:30 -0400
                Re: initialization of local static variable Barry Schwarz <schwarzb@dqel.com> - 2011-10-09 21:43 -0700
                Re: initialization of local static variable "io_x" <a@b.c.invalid> - 2011-10-10 19:08 +0200
                Re: initialization of local static variable Geoff <geoff@invalid.invalid> - 2011-10-10 16:16 -0700
                Re: initialization of local static variable Ike Naar <ike@iceland.freeshell.org> - 2011-10-10 23:22 +0000
                Re: initialization of local static variable James Kuyper <jameskuyper@verizon.net> - 2011-10-10 20:40 -0400
                Re: initialization of local static variable Barry Schwarz <schwarzb@dqel.com> - 2011-10-10 20:54 -0700
                Re: initialization of local static variable "io_x" <a@b.c.invalid> - 2011-10-11 18:45 +0200
                Re: initialization of local static variable "io_x" <a@b.c.invalid> - 2011-10-11 18:51 +0200
                Re: initialization of local static variable Barry Schwarz <schwarzb@dqel.com> - 2011-10-11 18:52 -0700
                Re: initialization of local static variable "io_x" <a@b.c.invalid> - 2011-10-12 08:49 +0200
                Re: initialization of local static variable "io_x" <a@b.c.invalid> - 2011-10-11 19:48 +0200
                Re: initialization of local static variable Barry Schwarz <schwarzb@dqel.com> - 2011-10-11 21:25 -0700
                Re: initialization of local static variable "io_x" <a@b.c.invalid> - 2011-10-12 08:48 +0200
                Re: initialization of local static variable "io_x" <a@b.c.invalid> - 2011-10-12 08:54 +0200
                Re: initialization of local static variable pete <pfiland@mindspring.com> - 2011-10-12 20:55 -0400
                Re: initialization of local static variable Barry Schwarz <schwarzb@dqel.com> - 2011-10-11 18:52 -0700
                Re: initialization of local static variable "io_x" <a@b.c.invalid> - 2011-10-11 19:55 +0200
                Re: initialization of local static variable Keith Thompson <kst-u@mib.org> - 2011-10-11 11:24 -0700
                Re: initialization of local static variable Keith Thompson <kst-u@mib.org> - 2011-10-11 12:47 -0700
                Re: initialization of local static variable "io_x" <a@b.c.invalid> - 2011-10-12 08:49 +0200
            Re: initialization of local static variable Tim Rentsch <txr@alumni.caltech.edu> - 2012-01-24 16:09 -0800
          Re: initialization of local static variable China Blue Corn Chips <chine.bleu@yahoo.com> - 2011-10-07 16:06 -0700
            Re: initialization of local static variable Seebs <usenet-nospam@seebs.net> - 2011-10-12 22:25 +0000
              Re: initialization of local static variable "christian.bau" <christian.bau@cbau.wanadoo.co.uk> - 2011-10-13 07:09 -0700
                Re: initialization of local static variable Seebs <usenet-nospam@seebs.net> - 2011-10-17 17:21 +0000
              Re: initialization of local static variable Joe Wright <joewwright@comcast.net> - 2011-10-14 14:27 -0400
          Re: initialization of local static variable Richard Damon <news.x.richarddamon@xoxy.net> - 2011-10-08 00:03 -0400
            Re: initialization of local static variable China Blue Corn Chips <chine.bleu@yahoo.com> - 2011-10-08 01:27 -0700
          Re: initialization of local static variable Richard Damon <news.x.richarddamon@xoxy.net> - 2011-10-08 00:08 -0400

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