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From: Keith Thompson <kst-u@mib.org>
Newsgroups: comp.lang.c
Subject: Re: Two C code questions
Date: Tue, 14 Mar 2017 11:49:58 -0700
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John Bode <jfbode1029@gmail.com> writes:
> On Monday, March 13, 2017 at 10:45:53 PM UTC-5, Mehdi Amini Valashani son of Bahram wrote:
[...]
>> int main(void)
>> {
>>      uint64_t ui[N] = {0};
>> 
>
> For C89 and earlier, array dimensions must be *constant expressions*; i.e.,
> something that can be evaluated at compile time (integer literals, sizeof
> expressions, macros that expand to either literals or sizeof expressions,
> arithmetic expressions that involve any of the previous, etc.).  
>
> A variable declared as "static const" is *not* a constant expression - its
> value is not evaluated at compile time.  
>
> C99 introduced variable-length arrays, whose size doesn't have to be 
> established until run time; if you compiled that code under a C99 compiler,
> it should work.  

No, C99 doesn't allow VLAs to be initialized (nor does C11).

-- 
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."
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