target/7371: code generation bug for mips-64

[Niels.Nes@cwi.nl]

>Number:         7371
>Category:       target
>Synopsis:       Negative offsets const arrays result in Sig BUS
>Confidential:   no
>Severity:       serious
>Priority:       low
>Responsible:    unassigned
>State:          open
>Class:          wrong-code
>Submitter-Id:   net
>Arrival-Date:   Mon Jul 22 05:26:01 PDT 2002
>Closed-Date:
>Last-Modified:
>Originator:     Niels Nes
>Release:        3.1
>Organization:
CWI
>Environment:
System: IRIX64 medusa 6.5 10100655 IP27


	
host: mips-sgi-irix6.5
build: mips-sgi-irix6.5
target: mips-sgi-irix6.5
configured with: ../configure --prefix=/soft/gcc-3.1
>Description:
	The following small example gives a SIG BUS when compiled with
	-mabi=64. Only happens with const arrays and a const offset. 
	In the assembly code a line .dword  a-16 combining
	the two can be found (possibly a problem on a mips (I'm not sure)).


#include <stdio.h>

static const int a [] = {
	0, 1, 4, 6, 
};

main(){
	int i = 0;
	
	for(i=4;i<8;i++){
		printf( "%d %d\n", i, a [i - 4] );
	}
}
>How-To-Repeat:
>Fix:
	Work around: remove the keyword const. 
>Release-Note:
>Audit-Trail:
>Unformatted: