[Bug tree-optimization/43670] New: "-fcompare-debug failure (length)" with -O -ftree-vrp

[Bug tree-optimization/43670] New: "-fcompare-debug failure (length)" with -O -ftree-vrp

[zsojka at seznam dot cz]

Command line:
gcc -O -ftree-vrp -m32 -fcompare-debug 20030324-1.c

Tested revisions:
r157965 - fail
r153685 - fail

Compiler output:
$ /mnt/svn/gcc-trunk/binary-157965-lto/bin/gcc -O -ftree-vrp -m32
-fcompare-debug testcase.c
gcc: testcase.c: -fcompare-debug failure (length)


-- 
           Summary: "-fcompare-debug failure (length)" with -O -ftree-vrp
           Product: gcc
           Version: 4.5.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: zsojka at seznam dot cz
  GCC host triplet: x86_64-pc-linux-gnu
GCC target triplet: i686-pc-linux-gnu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43670

[Bug tree-optimization/43670] "-fcompare-debug failure (length)" with -O -ftree-vrp

[zsojka at seznam dot cz]

------- Comment #1 from zsojka at seznam dot cz  2010-04-07 00:00 -------
Created an attachment (id=20324)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=20324&action=view)
reduced testcase

reduced from gcc/testsuite/gcc.dg/20030324-1.c

Command line:
gcc -O -ftree-vrp -m32 -fcompare-debug pr43670.c

-g results in different code being generated


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43670

[Bug tree-optimization/43670] "-fcompare-debug failure (length)" with -O -ftree-vrp

[jakub at gcc dot gnu dot org]

------- Comment #2 from jakub at gcc dot gnu dot org  2010-04-07 16:49 -------
Ugh, apparently nothing clears TREE_ADDRESSABLE on x when not -g, only with -g
(x really isn't addressable in the end).  So, here -g generates better code
than -g0.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43670

[Bug tree-optimization/43670] "-fcompare-debug failure (length)" with -O -ftree-vrp

[jakub at gcc dot gnu dot org]

------- Comment #3 from jakub at gcc dot gnu dot org  2010-04-07 17:00 -------
I've messed this up.  Of course it is the other way around, and it is
discover_nonconstant_array_refs that marks x TREE_ADDRESSABLE because of an
occurrence in DEBUG_STMT.  Sorry for the previous premature comment.


-- 

jakub at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |jakub at gcc dot gnu dot org
                   |dot org                     |
             Status|UNCONFIRMED                 |ASSIGNED
     Ever Confirmed|0                           |1
   Last reconfirmed|0000-00-00 00:00:00         |2010-04-07 17:00:43
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43670

[Bug debug/43670] [4.5/4.6 Regression] "-fcompare-debug failure (length)" with -O -ftree-vrp

[jakub at gcc dot gnu dot org]

-- 

jakub at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|"-fcompare-debug failure    |[4.5/4.6 Regression] "-
                   |(length)" with -O -ftree-vrp|fcompare-debug failure
                   |                            |(length)" with -O -ftree-vrp
   Target Milestone|---                         |4.5.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43670

[Bug debug/43670] "-fcompare-debug failure (length)" with -O -ftree-vrp

[jakub at gcc dot gnu dot org]

------- Comment #4 from jakub at gcc dot gnu dot org  2010-04-07 17:47 -------
Created an attachment (id=20329)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=20329&action=view)
gcc45-pr43670.patch

Untested fix.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43670

[Bug debug/43670] [4.5/4.6 Regression] "-fcompare-debug failure (length)" with -O -ftree-vrp

[jakub at gcc dot gnu dot org]

------- Comment #5 from jakub at gcc dot gnu dot org  2010-04-08 09:16 -------
Subject: Bug 43670

Author: jakub
Date: Thu Apr  8 09:16:28 2010
New Revision: 158108

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=158108
Log:
        PR debug/43670
        * cfgexpand.c (expand_debug_expr): If for non-NULL offset
        op0 is not a MEM, just return NULL instead of assertion
        failure.
        (discover_nonconstant_array_refs): Don't walk debug stmts.

        * gcc.dg/pr43670.c: New test.

Added:
    trunk/gcc/testsuite/gcc.dg/pr43670.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/cfgexpand.c
    trunk/gcc/testsuite/ChangeLog


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43670

[Bug debug/43670] [4.5/4.6 Regression] "-fcompare-debug failure (length)" with -O -ftree-vrp

[jakub at gcc dot gnu dot org]

------- Comment #6 from jakub at gcc dot gnu dot org  2010-04-08 09:18 -------
Subject: Bug 43670

Author: jakub
Date: Thu Apr  8 09:17:52 2010
New Revision: 158109

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=158109
Log:
        PR debug/43670
        * cfgexpand.c (expand_debug_expr): If for non-NULL offset
        op0 is not a MEM, just return NULL instead of assertion
        failure.
        (discover_nonconstant_array_refs): Don't walk debug stmts.

        * gcc.dg/pr43670.c: New test.

Added:
    branches/gcc-4_5-branch/gcc/testsuite/gcc.dg/pr43670.c
Modified:
    branches/gcc-4_5-branch/gcc/ChangeLog
    branches/gcc-4_5-branch/gcc/cfgexpand.c
    branches/gcc-4_5-branch/gcc/testsuite/ChangeLog


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43670

[Bug debug/43670] [4.5/4.6 Regression] "-fcompare-debug failure (length)" with -O -ftree-vrp

[jakub at gcc dot gnu dot org]

------- Comment #7 from jakub at gcc dot gnu dot org  2010-04-08 11:41 -------
Fixed.


-- 

jakub at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|                            |FIXED


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43670