Path: utzoo!utgpu!news-server.csri.toronto.edu!mailrus!uunet!nuchat!texhrc!ylc
From: ylc@texhrc.UUCP (Yin L. Cheung)
Newsgroups: comp.unix.ultrix
Subject: Re: Problems with CC on DECStation 3100
Summary: Check external variables
Message-ID: <502@texhrc.UUCP>
Date: 22 Sep 90 15:57:51 GMT
References: <68399@lll-winken.LLNL.GOV>
Distribution: na
Organization: Texaco Houston Res. Cntr Hou, Tx
Lines: 37


I've seen the "gp relocation" errors when external variables are
not declared and referenced consistently.  For example, when a variable is
declared as a structure and then externally referenced as a pointer to
structure.  "Lint" should uncover the inconsistency.  Below is an example
that generates "gp relocation" errors:

h1.h:
	typedef struct {
	    int len;
	    char data[256];
	} CountedString; 
c1.c:
	#include <stdio.h>
	#include "h1.h"
	CountedString cs = {5, "abcde"};
	func(ccs)
	    CountedString *ccs;
	{
	    int i;
	    for (i=0; i < ccs->len; i++) fputc(ccs->data[i], stdout);
	}
c2.c:
	#include "h1.h"
	extern CountedString *cs;
	main() {
	    func(&cs);
	}

Note that "cs" is declared inconsistently across c1.c and c2.c.  This
example will not link on the DS3100, but for reasons I don't understand
will link and run on a SPARCstation.

=======================
Yin Cheung, Texaco Inc.
convex!texhrc!ylc
=======================