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From: Keith Thompson <kst-u@mib.org>
Newsgroups: comp.lang.c
Subject: Re: error: initializer element is not constant|
Date: Tue, 09 May 2017 11:41:25 -0700
Organization: None to speak of
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Barry Schwarz <schwarzb@dqel.com> writes:
> On Tue, 9 May 2017 19:20:41 +0200, jak <please@nospam.tnx> wrote:
[...]
>>Ok. Then return to the first question. What information is missing from 
>>the compiler to solve this?
>>
>>char *Date = "01-01-80";
>>char *Phrase[] =
>>{
>>    NULL, /*1*/
>>    Date, /*2*/
>>    NULL, /*3*/
>>    NULL  /*4*/
>>};
>>
>>...and why does it solve this?
>>
>>char *DescDate = "Date: ";
>>char *Date = "01-01-80";
>>char *CrLf = "\r\n";
>>char *Text = "Dear friend...";
>>
>>char **Phrase[] =
>>{
>>   &DescDate, &Date, &CrLf,
>>   &Text, &CrLf
>>};
>
> Possibly because the address of a static variable is a compile time
> const (note const, not constant) while the value of a static variable
> is not.

You got that backwards.  The address of a static variable is a compile
time *constant*.  Specifically, it's an *address constant* as defined in
N1570 6.6p9.

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
Working, but not speaking, for JetHead Development, Inc.
"We must do something.  This is something.  Therefore, we must do this."
    -- Antony Jay and Jonathan Lynn, "Yes Minister"