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NNTP-Posting-Date: Sat, 04 Jun 2011 11:55:08 -0500
Message-ID: <4DEA636F.7BF2@mindspring.com>
Date: Sat, 04 Jun 2011 12:55:11 -0400
From: pete <pfiland@mindspring.com>
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Subject: Re: offsetof() Macro Attempt
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Xref: x330-a1.tempe.blueboxinc.net comp.lang.c:5436

Shao Miller wrote:
> 
> On 6/4/2011 5:49 AM, pete wrote:
> > Shao Miller wrote:
> >>
> >> On 6/3/2011 1:48 PM, pete wrote:
> >>> Shao Miller wrote:
> >>>
> >>>> So let's please go on to:
> >>>>
> >>>>      char ** helper;
> >>>>
> >>>>      enum foo {
> >>>>          bar = *helper + 1 - *helper
> >>>>        };
> >>>>
> >>>>      int main(void) {
> >>>>          return 0;
> >>>>        }

> > But even if (*helper) was defined,
> > then (*helper + 1 - *helper) is still not a constant expression

I should have said 'not an "integral constant expression"'

> > and the compiler that I'm using,
> > won't compile the above program.
> >
> 
> May I ask which compiler, please?  Since I am concerned about
> portability, that'd be great to know.  Thanks!

One of the ancient ones.

Microsoft Developer Studio 97
VC++ 5.0 

Compiling...
new.c
C:\Program Files\DevStudio\SharedIDE\bin\new.c(5) : error C2057:
expected constant expression
Error executing cl.exe.

new.obj - 1 error(s), 0 warning(s)


-- 
pete