Path: chuka.playstation.co.uk!news
From: sosman@terratron.com (Steven Osman)
Newsgroups: scea.yaroze.programming.gnu_compiler
Subject: Re: Linking
Date: Fri, 03 Dec 1999 03:38:18 GMT
Organization: PlayStation Net Yaroze (SCEE)
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Antony,

I would recommend using something to the effect of:

extern u_short Layout1[6];
in the .h file,

and putting the code you have written below in bg.c.  I am guessing
that you #include bg.h in both main.c and bg.c, correct?

The problem is that each time a .c file #includes bg.h, they will
define a new "copy" of Layout1, hence, your error.

As for your latter comment, I'm not certain why 
u_short Layout1[6];
would work.  To me, that looks like you are still redefining it.
Maybe it has something to do with the way the linker works/ including
statically initialized variables, and all...?  (Still, I don't think
EITHER should work).

On Thu, 2 Dec 1999 20:26:11 -0500, "Antony Arciuolo"
<antony.arciuolo@mail.trincoll.edu> wrote:

>I have an array to describe a layout (index) for a GsBG.
>
>I want to explicitly define it in the header of a BG module:
>
>#ifndef BG_H
>#define BG_H
>
>u_short Layout1[] =
>{ 
>GsCELLtransparentCell, GsCELLtransparentCell, 
>GsCELLtransparentCell, GsCELLtransparentCell, 
>GsCELLtransparentCell, GsCELLtransparentCell
>};
>
>...
>#endif
>
>Now I want to compile using this makefile
>
>
>PROGRAM = test.pxe
>PXE_ADDR = 80140000
>
># To Optimize use -O3 instead of -g
>OPTIONS = -c -g
>LINKER = -Xlinker -Map -Xlinker mapfile.map -Xlinker -Ttext -Xlinker $(PXE_ADDR)
>DEPENDENCIES = bg.o main.o
>
>all: $(PROGRAM)
>
>$(PROGRAM): $(PROGOBJ) $(DEPENDENCIES)
> gcc $(LINKER) $(DEPENDENCIES) -o $(PROGRAM)
>
>main.o: main.c mainTIMS.h Levels.h
> gcc $(OPTIONS) main.c
>
>bg.o: bg.c bg.h Levels.h
> gcc $(OPTIONS) bg.c
>
>The problem is:
>
>gcc -Xlinker -Map -Xlinker mapfile.map -Xlinker -Ttext -Xlinker 80140000 bg.o main.o -o test.pxe
>main.o(.data+0x0): multiple definition of `Layout1'
>bg.o(.data+0x0): first defined here
>make.exe: *** [test.pxe] Error 1
>
>How can I solve this? It just does not seem to me that it is being defined twice, and if I redeclare Layout1 as:
>
>
>u_short Layout1[6];
>
>Everything is fine. Why?
>
>- Tony
>
>
>
>