[Bug rtl-optimization/45136] New: -fcompare-debug failure with -Os -fschedule-insns

[Bug rtl-optimization/45136] New: -fcompare-debug failure with -Os -fschedule-insns

[zsojka at seznam dot cz]

Output:
$ gcc -Os -fschedule-insns -fcompare-debug testcase.c
gcc: error: testcase.c: -fcompare-debug failure

Tested revisions:
r162653 - fail
r161170 - fail
r153685 - fail


-- 
           Summary: -fcompare-debug failure with -Os -fschedule-insns
           Product: gcc
           Version: 4.6.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: rtl-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: x86_64-pc-linux-gnu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45136

[Bug rtl-optimization/45136] -fcompare-debug failure with -Os -fschedule-insns

[zsojka at seznam dot cz]

------- Comment #1 from zsojka at seznam dot cz  2010-07-29 20:21 -------
Created an attachment (id=21356)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=21356&action=view)
reduced testcase

Valgrind doesn't report any invalid/uninitialised read while compiling this
testcase.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45136

[Bug rtl-optimization/45136] -fcompare-debug failure with -Os -fschedule-insns

[hjl dot tools at gmail dot com]

------- Comment #2 from hjl dot tools at gmail dot com  2010-07-30 00:32 -------
It is caused by revision 161655:

http://gcc.gnu.org/ml/gcc-cvs/2010-07/msg00006.html


-- 

hjl dot tools at gmail dot com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |rguenth at gcc dot gnu dot
                   |                            |org
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|0                           |1
   Last reconfirmed|0000-00-00 00:00:00         |2010-07-30 00:32:50
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45136

[Bug rtl-optimization/45136] -fcompare-debug failure with -Os -fschedule-insns

[zsojka at seznam dot cz]

------- Comment #3 from zsojka at seznam dot cz  2010-07-30 01:35 -------
Thank you for the reply! Then, the bug had to be fixed/hiden before r161655, I
can reproduce it with r161170, r153685 and gcc 4.5.0. (maybe you replied to a
wrong PR?)


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45136

[Bug rtl-optimization/45136] -fcompare-debug failure with -Os -fschedule-insns

[hjl dot tools at gmail dot com]

------- Comment #4 from hjl dot tools at gmail dot com  2010-07-30 04:11 -------
I was wrong. It never worked.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45136

[Bug rtl-optimization/45136] -fcompare-debug failure with -Os -fschedule-insns

[jakub at gcc dot gnu dot org]

------- Comment #5 from jakub at gcc dot gnu dot org  2010-07-30 09:40 -------
Confirmed, this seems to be sched1 fault.
In bb5 we have 2 normal insns, followed by (-g only) a debug_insn, followed by
two NOTE_INSN_DELETED created by combine (do we ever remove these from the
IL?),
followed again (-g only) by debug_insn and then other insns.
sched1 moves those two NOTE_INSN_DELETED in -g case to the start of the block,
keeps them where they were otherwise.

Alex, can you please have a look?


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45136

[Bug rtl-optimization/45136] -fcompare-debug failure with -Os -fschedule-insns

[aoliva at gcc dot gnu dot org]

------- Comment #6 from aoliva at gcc dot gnu dot org  2010-08-30 19:13 -------
The debug insns aren't at the end of the block in the beginning of sched, so we
don't disregard them at first, but they become end-of-block insns after the
trailing non-debug insns are pulled into other earlier blocks in the same
region.  I'm testing a patch that revamps the way we deal with boundary notes
and debug insns.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45136

[Bug rtl-optimization/45136] -fcompare-debug failure with -Os -fschedule-insns

[aoliva at gcc dot gnu dot org]

------- Comment #7 from aoliva at gcc dot gnu dot org  2010-08-30 19:14 -------
The debug insns aren't at the end of the block in the beginning of sched, so we
don't disregard them at first, but they become end-of-block insns after the
trailing non-debug insns are pulled into other earlier blocks in the same
region.  I'm testing a patch that revamps the way we deal with boundary notes
and debug insns.


-- 

aoliva at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |aoliva at gcc dot gnu dot
                   |dot org                     |org
             Status|NEW                         |ASSIGNED


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45136

[Bug debug/45136] -fcompare-debug failure with -Os -fschedule-insns

[aoliva at gcc dot gnu dot org]

------- Comment #8 from aoliva at gcc dot gnu dot org  2010-09-04 15:28 -------
*** Bug 45130 has been marked as a duplicate of this bug. ***


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45136