[Bug c/37044] New: Heisenbug: SVN of gcc throws internal compiler error on PPC

[Bug c/37044] New: Heisenbug: SVN of gcc throws internal compiler error on PPC

[contact at multimedia dot cx]

For several months, I have been keeping abreast of recent gcc-SVN builds on
several platforms for automatically building and testing a certain free
software project. The build for PowerPC has intermittently given internal
compiler errors. It has been difficult to nail down because the internal error
might go away depending on the state of the project source tree being compiled.

I usually rebuild the gcc-SVN copies once every 1-3 weeks. The gcc build
process follows this pattern:

'svn update' in my local copy of the gcc tree
'mkdir build-gcc' in an unrelated directory
'/path/to/gcc-svn/configure --enable-languages=c
--prefix=/usr/local/gcc-138544-20080801' -- this reflects the last build I
made: SVN revision 138544, built on 2008-08-01

So I build and install the C compiler. When I compile the program in question
(ffmpeg) and the build fails, it happens on one of a few files. With the build
mentioned above, this command fails:

 /usr/local/gcc-138544-20080801/bin/gcc -DHAVE_AV_CONFIG_H
-D_FILE_OFFSET_BITS=64 -D_LARGEFILE_SOURCE -D_ISOC9X_SOURCE -I.
-I"/home/melanson/ffmpeg/ffmpeg-main" -fomit-frame-pointer -maltivec
-mabi=altivec -Wdeclaration-after-statement -Wall -Wno-switch
-Wdisabled-optimization -Wpointer-arith -Wredundant-decls -Wno-pointer-sign
-Wcast-qual -Wwrite-strings -Wtype-limits -O3 -fno-math-errno -fno-signed-zeros
       -fPIC -DPIC -c -o libavcodec/dca.o
/home/melanson/ffmpeg/ffmpeg-main/libavcodec/dca.c

This is the error:

/home/melanson/ffmpeg/ffmpeg-main/libavcodec/dca.c: In function
'dca_subsubframe':
/home/melanson/ffmpeg/ffmpeg-main/libavcodec/dca.c:941: warning: array
subscript is above array bounds
/home/melanson/ffmpeg/ffmpeg-main/libavcodec/dca.c:941: warning: array
subscript is above array bounds
/home/melanson/ffmpeg/ffmpeg-main/libavcodec/dca.c:941: warning: array
subscript is above array bounds
/home/melanson/ffmpeg/ffmpeg-main/libavcodec/dca.c: In function
'dca_decode_frame':
/home/melanson/ffmpeg/ffmpeg-main/libavcodec/dca.c:1200: internal compiler
error: in tree_node_structure, at tree.c:2412
Please submit a full bug report,
with preprocessed source if appropriate.
See <http://gcc.gnu.org/bugs.html> for instructions.

Now here's the Heisenbug unpredictability: I added -save-temps as requested on
the bug page. The compiler does not crash.

I'm working on a new PPC compiler build right now. I just wanted to finally
enter this bug as a placeholder. I hope to have more data soon.


-- 
           Summary: Heisenbug: SVN of gcc throws internal compiler error on
                    PPC
           Product: gcc
           Version: 4.4.0
            Status: UNCONFIRMED
          Severity: major
          Priority: P3
         Component: c
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: contact at multimedia dot cx
 GCC build triplet: powerpc-unknown-linux-gnu
  GCC host triplet: powerpc-unknown-linux-gnu
GCC target triplet: powerpc-unknown-linux-gnu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37044

[Bug c/37044] Heisenbug: SVN of gcc throws internal compiler error on PPC

[contact at multimedia dot cx]

------- Comment #1 from contact at multimedia dot cx  2008-08-07 05:30 -------
The same thing happens with gcc SVN-138833 (along with FFmpeg SVN 14654)--
dca.c file compilation crashes but not with -save-temps.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37044

Re: [Bug c/37044] Heisenbug: SVN of gcc throws internal compiler error on PPC

[Andrew Thomas Pinski]

Sent from my iPhone

On Aug 6, 2008, at 22:30, "contact at multimedia dot cx" <gcc-bugzilla@gcc.gnu.org 
 > wrote:

>
>
> ------- Comment #1 from contact at multimedia dot cx  2008-08-07  
> 05:30 -------
> The same thing happens with gcc SVN-138833 (along with FFmpeg SVN  
> 14654)--
> dca.c file compilation crashes but not with -save-temps.
>

Please attach the preprocessed source.  This is most likely a GC issue.

-- Pinski



>
> -- 
>
>
> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37044
>

[Bug c/37044] Heisenbug: SVN of gcc throws internal compiler error on PPC

[pinskia at gmail dot com]

------- Comment #2 from pinskia at gmail dot com  2008-08-07 05:48 -------
Subject: Re:  Heisenbug: SVN of gcc throws internal compiler error on PPC



Sent from my iPhone

On Aug 6, 2008, at 22:30, "contact at multimedia dot cx"
<gcc-bugzilla@gcc.gnu.org 
 > wrote:

>
>
> ------- Comment #1 from contact at multimedia dot cx  2008-08-07  
> 05:30 -------
> The same thing happens with gcc SVN-138833 (along with FFmpeg SVN  
> 14654)--
> dca.c file compilation crashes but not with -save-temps.
>

Please attach the preprocessed source.  This is most likely a GC issue.

-- Pinski



>
> -- 
>
>
> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37044
>


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37044

[Bug c/37044] Heisenbug: SVN of gcc throws internal compiler error on PPC

[contact at multimedia dot cx]

------- Comment #3 from contact at multimedia dot cx  2008-08-08 03:25 -------
Created an attachment (id=16042)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=16042&action=view)
Preprocessor output for file that is crashing compiler

As requested, this is the preprocessed output when adding -save-temps to the
command line in the original bug post.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37044

[Bug middle-end/37044] Heisenbug: SVN of gcc throws internal compiler error on PPC

[pinskia at gcc dot gnu dot org]

-- 

pinskia at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Severity|major                       |normal
          Component|c                           |middle-end
           Keywords|                            |ice-on-valid-code


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37044

[Bug middle-end/37044] Heisenbug: SVN of gcc throws internal compiler error on PPC

[pinskia at gcc dot gnu dot org]

------- Comment #4 from pinskia at gcc dot gnu dot org  2008-09-03 02:49 -------
I want to say this was really fixed by:
2008-07-24  Ben Elliston  <bje@au.ibm.com>

        * config/rs6000/rs6000-c.c: Move GTY(()) markers to match
        conventional usage.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37044

[Bug middle-end/37044] Heisenbug: SVN of gcc throws internal compiler error on PPC

[contact at multimedia dot cx]

------- Comment #5 from contact at multimedia dot cx  2008-09-04 15:13 -------
Perhaps the change should have, but it didn't. The problem still manifests with
SVN 139974 (latest as of yesterday).


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37044

[Bug middle-end/37044] Heisenbug: SVN of gcc throws internal compiler error on PPC

[pinskia at gcc dot gnu dot org]

------- Comment #6 from pinskia at gcc dot gnu dot org  2008-12-27 14:51 -------


*** This bug has been marked as a duplicate of 38553 ***


-- 

pinskia at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|                            |DUPLICATE


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37044