Date:	Wed, 15 Oct 1997 18:28:28 +1100
From:	Bill Currie <billc AT blackmagic DOT tait DOT co DOT nz>
Subject:	Re: Is this a bug ??? or feature ??
In-reply-to:	<19971014223300.SAA13822@ladder01.news.aol.com>
To:	br5an AT aol DOT com (Br5an), djgpp AT delorie DOT com
Message-id:	<199710150525.SAA15914@teleng1.tait.co.nz gatekeeper.tait.co.nz>
Organization:	Tait Electronics Limited
MIME-version:	1.0
Comments:	Authenticated sender is <billc AT blackmagic DOT tait DOT co DOT nz>

On 14 Oct 97 at 22:33, Br5an wrote:

> Guan Foo Wah wrote:
> snip:
> >This is the output compiled on the DJGPP compiler (using BNU281B.ZIP)
> 
> >Address : 155b 155b 155b
> >Value before modifying : one one one
> >Value after modifying  : fne fne fne
> 
> >and this is the output compiled on the TURBO C v3.0
> 
> >Address : 00BC 00C0 00D7
> >Value before modifying : one one one
> >Value after modifying  : fne one one
> 

[snip]

> 
> Guan Foo Wah,
>      I can't be sure without experimenting some but it sounds like
>      the compiler
>  is optimizing duplicate strings. You will find this is an option

This is correct.

>  with Turbo C++ 3.0  (Options / Compiler / Code Generation).  For
>  now all I can suggest is to declare your arrays, and then to set
>  there contents later in the code (inside main?) and see if that
>  helps. Hopefully someone else may come through with how to disable
>  the optimization (if that's the case) or with another idea.

Simple, don't use pointers, use actuall arrays, eg:

char num_1[]="foo";
char num_2[]="foo";
char num_3[]="foo";

char *num[]={num_1,num_2,num_3};

int main()
{
	int i;
	for (i=0; i<3; i++) {
		printf("%p %s\n",num[i],num[i]);
	}
	strcpy(num[0],"bar");
	for (i=0; i<3; i++) {
		printf("%p %s\n",num[i],num[i]);
	}
	return 0;
}

Will give you the exepected results;

Bill
--
Leave others their otherness.

- Raw text -