RE: [Sdcc-user] Multiple declaration of strings

[Bernhard H. <ber...@ot...>]

>
>Hello all,
>     I've encountered the following problem when defining some text-strings in 
>a library (*.h) file.
>
>I declare them as:
>
>#ifndef _STRINGS_H_>
>#define _STRINGS_H_
>code unsigned char string[] = "some piece of text";
>xdata unsigned char string2[] = "another piece of text";
>
>#endif // _STRINGS_H_
>
>After compiling and loading it into my microcontroller, I see that they are 
>declared at the start and end of my code (when browsing codespace). Why is 
>that? How can I avoid this waste of codespace?
>
>When I declare them into the sourcefile directly, they are only declared once, 
>but some of them I need in multiple sourcefiles.
>Sometimes the compiler gives a warning about it (declaring these things 
>twice), sometimes (mostly?) not.

You shouldn't >define< anything in a header. Headers should be used to >declare< something. Consider the difference. The advantage: if you include the header several times, you won't have any trouble with multiple defined things.

Your header mystring.h could look like:

#ifndef _STRINGS_H_>
#define _STRINGS_H_
extern code unsigned char *string;
extern xdata unsigned char *string2;

#endif // _STRINGS_H_


Put the defines in a second file mystring.c:

#include "mystring.h"

code unsigned char *string = "some piece of text";
xdata unsigned char *string2 = "another piece of text";


Bernhard