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* [Bug c/37665]  New: invalid loop generation
@ 2008-09-27 21:01 joel at gcc dot gnu dot org
  2008-09-27 21:02 ` [Bug c/37665] " joel at gcc dot gnu dot org
  0 siblings, 1 reply; 2+ messages in thread
From: joel at gcc dot gnu dot org @ 2008-09-27 21:01 UTC (permalink / raw)
  To: gcc-bugs

At optimization levels -Os, -O1, and -O2, the attached program generates
incorrect loop code.  It appears that when optimizing, the loop termination is
checking array end address versus current pointer.  The array end address
contains all address bits while the current pointer is just the lower (16?)
bits.

m32c-elf-gcc -O1 -mcpu=m32cm -msim m1.c && m32c-elf-run a.out 
NULL pointer dereference

Attaching test program.


-- 
           Summary: invalid loop generation
           Product: gcc
           Version: 4.4.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: joel at gcc dot gnu dot org
GCC target triplet: m32c-elf


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37665


^ permalink raw reply	[flat|nested] 2+ messages in thread
* [Bug c/37665] invalid loop generation
  2008-09-27 21:01 [Bug c/37665] New: invalid loop generation joel at gcc dot gnu dot org
@ 2008-09-27 21:02 ` joel at gcc dot gnu dot org
  0 siblings, 0 replies; 2+ messages in thread
From: joel at gcc dot gnu dot org @ 2008-09-27 21:02 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #1 from joel at gcc dot gnu dot org  2008-09-27 21:00 -------
Created an attachment (id=16417)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=16417&action=view)
small test program

test program demonstrating problem


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37665


^ permalink raw reply	[flat|nested] 2+ messages in thread
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2008-09-27 21:01 [Bug c/37665] New: invalid loop generation joel at gcc dot gnu dot org
2008-09-27 21:02 ` [Bug c/37665] " joel at gcc dot gnu dot org

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