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Bug 000072

When Created: 04/07/1996 06:08:17
Against DJGPP version: 2.00
By whom: mc5686@mclink.it
Abstract: -fstrenth-reduce bug fixed, we can correct specs
I downloaded latest version of djgpp (with gcc2.72) and i see that 
specs are still defining -no-strength-reduce.

This bug has been fixed in the Linux community.

This is the patch that fixes the bug:

===================================
Date sent:       	Thu, 11 Jan 1996 21:08:15 +1000
From:            	Tony Nugent <tonyn@sctnugen.ppp.gu.edu.au>
To:              	linux-kernel@vger.rutgers.edu, lkinley@frugal.Com
Subject:          Re: gcc 2.7.2 -fno-strength-reduce bug...

Lance Kinley <lkinley@frugal.Com> wrote on Tue, 2 Jan 1996:

> I appear to have deleted ALL the messages with the patch for this bug.  
> (I thought I kept at least one of them...oh well)  Can someone mail me 
> the patch, please?

*** gcc-2.7.0/loop.c	Thu Sep  7 10:35:36 1995
--- gcc-2.7.0-x/loop.c	Thu Sep  7 10:32:38 1995
*************** maybe_eliminate_biv_1 (x, insn, bl, elim
*** 6130,6135 ****
--- 6130,6140 ----
   {
     if (invariant_p (arg) == 1)
       {
+ #if 0	      /* Linear transformations of the compared values
+ 		 are incorrect unless it can be verified that
+ 		 overflow behaviour stays the same for all possible
+ 		 values of the loop bound, for all iterations. */
+ 
         /* Look for giv with constant positive mult_val and nonconst
     add_val. Insert insns to compute new compare value.  */

*************** maybe_eliminate_biv_1 (x, insn, bl, elim
*** 6156,6161 ****
--- 6161,6167 ----
        if (apply_change_group ())
          return 1;
      }
+ #endif
       }

     /* This code has problems.  Basically, you can't know when

===================================

Is this patch already in (i didn't fetch the sources, yet)??
If so we can correct  ../lib/specs; if not we have better apply it (IMHO).

Many thanks for the GOOOOD work.

Ciao 
Mauro

Note added: 09/04/1996 10:43:19
By whom: terra@diku.dk
gcc 2.7.2.1 alledgedly fixes this.

Solution added: 04/13/1999 08:00:21
By whom: eliz@is.elta.co.il
Upgrade to DJGPP v2.02.

Fixed in version on 04/13/1999 08:00:53
By whom: eliz@is.elta.co.il



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