[Bug bootstrap/54926] New: [4.8 Regression] Bootstrap comparison failure for various files in libbacktrace

[Bug bootstrap/54926] New: [4.8 Regression] Bootstrap comparison failure for various files in libbacktrace

[danglin at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54926

             Bug #: 54926
           Summary: [4.8 Regression] Bootstrap comparison failure for
                    various files in libbacktrace
    Classification: Unclassified
           Product: gcc
           Version: 4.8.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: bootstrap
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: danglin@gcc.gnu.org
                CC: uros@gcc.gnu.org
              Host: hppa2.0w-hp-hpux11.11
            Target: hppa2.0w-hp-hpux11.11
             Build: hppa2.0w-hp-hpux11.11


Bootstrap comparison failure!
libbacktrace/.libs/dwarf.o differs
libbacktrace/.libs/fileline.o differs
libbacktrace/.libs/posix.o differs
libbacktrace/.libs/print.o differs
libbacktrace/.libs/state.o differs
libbacktrace/.libs/backtrace.o differs
libbacktrace/.libs/simple.o differs
libbacktrace/.libs/unknown.o differs
libbacktrace/.libs/mmapio.o differs
libbacktrace/.libs/mmap.o differs
make[2]: *** [compare] Error 1
make[2]: Leaving directory `/test/gnu/gcc/objdir'
make[1]: *** [stage3-bubble] Error 2
make[1]: Leaving directory `/test/gnu/gcc/objdir'
make: *** [bootstrap] Error 2
Sun Oct 14 17:26:48 EDT 2012

# ./xgcc -B./ -v
Reading specs from ./specs
COLLECT_GCC=./xgcc
COLLECT_LTO_WRAPPER=./lto-wrapper
Target: hppa2.0w-hp-hpux11.11
Configured with: ../gcc/configure --with-gnu-as --with-as=/opt/gnu/bin/as
--enable-shared --with-local-prefix=/opt/gnu --prefix=/opt/gnu/gcc/gcc-4.8
--with-gmp=/opt/gnu/gcc/gmp --enable-threads=posix --enable-debug=no
--disable-nls --disable-lto --without-cloog --without-ppl
--enable-languages=c,c++,objc,fortran,java,ada,obj-c++
Thread model: posix
gcc version 4.8.0 20121014 (experimental) [trunk revision 192432] (GCC) 

Problem was introduced in r191981.

# od -c stage3-libbacktrace/.libs/mmap.o >mmap.o.dump3                 
# od -c stage2-libbacktrace/.libs/mmap.o >mmap.o.dump2
# /opt/gnu/bin/diff -u mmap.o.dump2 mmap.o.dump3|less 
--- mmap.o.dump2        Sun Oct 14 18:11:19 2012
+++ mmap.o.dump3        Sun Oct 14 18:11:06 2012
@@ -1427,7 +1427,7 @@
 0054440   B   A   L   _   _   F   _   .   .   _   .   .   _   g   c   c
 0054460   _   l   i   b   b   a   c   k   t   r   a   c   e   _   m   m
 0054500   a   p   .   c   _   5   6   A   F   5   6   2   3   _   0   x
-0054520   6   0   3   1   b   f   a   b  \0  \0  \0  \0  \0  \0  \0 006
+0054520   6   0   b   7   9   d   9   8  \0  \0  \0  \0  \0  \0  \0 006
 0054540   $   D   A   T   A   $  \0  \0  \0  \0  \0 006   $   C   O   D
 0054560   E   $  \0  \0  \0  \0  \0 006   $   C   O   D   E   $  \0  \0
 0054600  \0  \0  \0 006   $   C   O   D   E   $  \0  \0  \0  \0  \0 006

# nm stage3-libbacktrace/.libs/mmap.o >mmap.o.dump3   
# nm stage2-libbacktrace/.libs/mmap.o >mmap.o.dump2
# /opt/gnu/bin/diff -u mmap.o.dump2 mmap.o.dump3|less
--- mmap.o.dump2        Sun Oct 14 18:13:24 2012
+++ mmap.o.dump3        Sun Oct 14 18:13:14 2012
@@ -6,7 +6,7 @@
 00000000 t $CODE$
 00000000 t $CODE$
 40000000 d $DATA$
-40000000 D _GLOBAL__F_.._.._gcc_libbacktrace_mmap.c_56AF5623_0x6031bfab
+40000000 D _GLOBAL__F_.._.._gcc_libbacktrace_mmap.c_56AF5623_0x60b79d98
          U abort
 00000000 T backtrace_alloc
 00000000 T backtrace_free

Problem is random destructor symbol names in files.

[Bug bootstrap/54926] [4.8 Regression] Bootstrap comparison failure for various files in libbacktrace

[ubizjak at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54926

--- Comment #1 from Uros Bizjak <ubizjak at gmail dot com> 2012-10-15 06:44:57 UTC ---
(In reply to comment #0)

> Problem was introduced in r191981.

The patch just introduces -funwind-tables to compile flags, so I really don't
see how this can cause any difference.

[Bug bootstrap/54926] [4.8 Regression] Bootstrap comparison failure for various files in libbacktrace

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54926

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |4.8.0

[Bug bootstrap/54926] [4.8 Regression] Bootstrap comparison failure for various files in libbacktrace

[dave.anglin at bell dot net]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54926

--- Comment #2 from dave.anglin at bell dot net 2012-10-15 11:55:29 UTC ---
On 15-Oct-12, at 2:44 AM, ubizjak at gmail dot com wrote:

> The patch just introduces -funwind-tables to compile flags, so I  
> really don't
> see how this can cause any difference.

I hacked configure to turn -funwind-tables off on hpux.  It is the  
cause of the comparison
difference.

The difference isn't caused by incorrect code.  Think the compare  
needs to be ignored
on hpux.

Dave
--
John David Anglin    dave.anglin@bell.net

[Bug bootstrap/54926] [4.8 Regression] Bootstrap comparison failure for various files in libbacktrace

[danglin at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54926

John David Anglin <danglin at gcc dot gnu.org> changed:

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

--- Comment #3 from John David Anglin <danglin at gcc dot gnu.org> 2012-11-29 20:49:29 UTC ---
Fixed.

[Bug bootstrap/54926] [4.8 Regression] Bootstrap comparison failure for various files in libbacktrace

[danglin at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54926

John David Anglin <danglin at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|RESOLVED                    |REOPENED
   Last reconfirmed|                            |2012-12-02
         Resolution|FIXED                       |
     Ever Confirmed|0                           |1

--- Comment #4 from John David Anglin <danglin at gcc dot gnu.org> 2012-12-02 17:17:06 UTC ---
Comment #3 is incorrect.  Thought the configure change to check
for -funwind-tables support fixed the compare failure, it turns
out it doesn't disable unwind-table support.

[Bug bootstrap/54926] [4.8 Regression] Bootstrap comparison failure for various files in libbacktrace

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54926

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P3                          |P1

[Bug bootstrap/54926] [4.8 Regression] Bootstrap comparison failure for various files in libbacktrace

[dave.anglin at bell dot net]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54926

--- Comment #5 from dave.anglin at bell dot net 2012-12-03 16:06:22 UTC ---
I have a patch to ignore the comparison failure and a couple changes to 
libbacktrace
for hpux.  The btest program now runs successfully on hpux. However, 
backtrace still
doesn't work from within compiler.

[Bug bootstrap/54926] [4.8 Regression] Bootstrap comparison failure for various files in libbacktrace

[dave.anglin at bell dot net]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54926

--- Comment #6 from dave.anglin at bell dot net 2012-12-03 22:33:39 UTC ---
On 12/3/2012 11:06 AM, John David Anglin wrote:
>  However, backtrace still doesn't work from within compiler.
>

Problem is with fileline_initialize.  The techniques currently being used to
obtain the full pathname of the executable don't work on HP-UX.
http://www.cplusplus.com/forum/general/11104/

Dave

[Bug bootstrap/54926] [4.8 Regression] Bootstrap comparison failure for various files in libbacktrace

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54926

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|REOPENED                    |WAITING
                 CC|                            |jakub at gcc dot gnu.org

--- Comment #7 from Jakub Jelinek <jakub at gcc dot gnu.org> 2012-12-06 18:39:03 UTC ---
For the bootstrap comparison failures, I'd guess libbacktrace should be built
with
-frandom-seed=$@
in CFLAGS similarly how libstdc++-v3 is built.
In what way doesn't backtrace work in the compiler?  Does it crash, or not
print any backtrace?  The former would be a regression, the latter would not. 
So, does:
2012-12-06  Jakub Jelinek  <jakub@redhat.com>

    PR bootstrap/54926
    * Makefile.am (AM_CFLAGS): Add -frandom-seed=$@.
    * Makefile.in: Regenerated.

--- libbacktrace/Makefile.am.jj    2012-10-02 15:36:21.000000000 +0200
+++ libbacktrace/Makefile.am    2012-12-06 19:36:05.888001803 +0100
@@ -34,7 +34,7 @@ ACLOCAL_AMFLAGS = -I .. -I ../config
 AM_CPPFLAGS = -I $(top_srcdir)/../include -I $(top_srcdir)/../libgcc \
     -I ../libgcc -I ../gcc/include -I $(MULTIBUILDTOP)../../gcc/include

-AM_CFLAGS = $(EXTRA_FLAGS) $(WARN_FLAGS) $(PIC_FLAG)
+AM_CFLAGS = $(EXTRA_FLAGS) $(WARN_FLAGS) $(PIC_FLAG) -frandom-seed=$@

 noinst_LTLIBRARIES = libbacktrace.la

--- libbacktrace/Makefile.in.jj    2012-10-02 15:36:21.000000000 +0200
+++ libbacktrace/Makefile.in    2012-12-06 19:36:26.284875521 +0100
@@ -254,7 +254,7 @@ ACLOCAL_AMFLAGS = -I .. -I ../config
 AM_CPPFLAGS = -I $(top_srcdir)/../include -I $(top_srcdir)/../libgcc \
     -I ../libgcc -I ../gcc/include -I $(MULTIBUILDTOP)../../gcc/include

-AM_CFLAGS = $(EXTRA_FLAGS) $(WARN_FLAGS) $(PIC_FLAG)
+AM_CFLAGS = $(EXTRA_FLAGS) $(WARN_FLAGS) $(PIC_FLAG) -frandom-seed=$@
 noinst_LTLIBRARIES = libbacktrace.la
 libbacktrace_la_SOURCES = \
     backtrace.h \

patch fix all the regressions, turning this just into enhancement request to
support libbacktrace better on HP-UX?

[Bug bootstrap/54926] [4.8 Regression] Bootstrap comparison failure for various files in libbacktrace

[aoliva at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54926

Alexandre Oliva <aoliva at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |aoliva at gcc dot gnu.org

--- Comment #8 from Alexandre Oliva <aoliva at gcc dot gnu.org> 2012-12-06 21:45:02 UTC ---
Jakub, the configury patch is ok, thanks.

[Bug bootstrap/54926] [4.8 Regression] Bootstrap comparison failure for various files in libbacktrace

[dave.anglin at bell dot net]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54926

--- Comment #9 from dave.anglin at bell dot net 2012-12-07 13:33:16 UTC ---
On 6-Dec-12, at 1:39 PM, jakub at gcc dot gnu.org wrote:

>
> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54926
>
> Jakub Jelinek <jakub at gcc dot gnu.org> changed:
>
>           What    |Removed                     |Added
> ----------------------------------------------------------------------------
>             Status|REOPENED                    |WAITING
>                 CC|                            |jakub at gcc dot  
> gnu.org
>
> --- Comment #7 from Jakub Jelinek <jakub at gcc dot gnu.org>  
> 2012-12-06 18:39:03 UTC ---
> For the bootstrap comparison failures, I'd guess libbacktrace should  
> be built
> with
> -frandom-seed=$@
> in CFLAGS similarly how libstdc++-v3 is built.
> In what way doesn't backtrace work in the compiler?  Does it crash,  
> or not
> print any backtrace?  The former would be a regression, the latter  
> would not.
> So, does:
> 2012-12-06  Jakub Jelinek  <jakub@redhat.com>
>
>    PR bootstrap/54926
>    * Makefile.am (AM_CFLAGS): Add -frandom-seed=$@.
>    * Makefile.in: Regenerated.
>
> --- libbacktrace/Makefile.am.jj    2012-10-02 15:36:21.000000000 +0200
> +++ libbacktrace/Makefile.am    2012-12-06 19:36:05.888001803 +0100
> @@ -34,7 +34,7 @@ ACLOCAL_AMFLAGS = -I .. -I ../config
> AM_CPPFLAGS = -I $(top_srcdir)/../include -I $(top_srcdir)/../libgcc \
>     -I ../libgcc -I ../gcc/include -I $(MULTIBUILDTOP)../../gcc/ 
> include
>
> -AM_CFLAGS = $(EXTRA_FLAGS) $(WARN_FLAGS) $(PIC_FLAG)
> +AM_CFLAGS = $(EXTRA_FLAGS) $(WARN_FLAGS) $(PIC_FLAG) -frandom-seed=$@
>
> noinst_LTLIBRARIES = libbacktrace.la
>
> --- libbacktrace/Makefile.in.jj    2012-10-02 15:36:21.000000000 +0200
> +++ libbacktrace/Makefile.in    2012-12-06 19:36:26.284875521 +0100
> @@ -254,7 +254,7 @@ ACLOCAL_AMFLAGS = -I .. -I ../config
> AM_CPPFLAGS = -I $(top_srcdir)/../include -I $(top_srcdir)/../libgcc \
>     -I ../libgcc -I ../gcc/include -I $(MULTIBUILDTOP)../../gcc/ 
> include
>
> -AM_CFLAGS = $(EXTRA_FLAGS) $(WARN_FLAGS) $(PIC_FLAG)
> +AM_CFLAGS = $(EXTRA_FLAGS) $(WARN_FLAGS) $(PIC_FLAG) -frandom-seed=$@
> noinst_LTLIBRARIES = libbacktrace.la
> libbacktrace_la_SOURCES = \
>     backtrace.h \
>
> patch fix all the regressions, turning this just into enhancement  
> request to
> support libbacktrace better on HP-UX?


The patch fixes the bootstrap comparison failure but I wouldn't say it  
fixes all the regressions.
See attached patch.

1) The MAP_FAILED change to mmapio.c is needed to build successfully  
on HP-UX 10.
2) The HAVE_SYNC_FUNCTIONS change fixes an abort which regresses the  
handling
of ICEs.

The change to filename.c improves libbacktrace support on HP-UX  
systems using ELF
binaries.  With this change, I get a successful backtrace.  For example,

spawn /test/gnu/gcc/objdir/gcc/xgcc -B/test/gnu/gcc/objdir/gcc/ /test/ 
gnu/gcc/gc
c/gcc/testsuite/gcc.c-torture/execute/pr51447.c -fno-diagnostics-show- 
caret -w -
O2 -lm -o /test/gnu/gcc/objdir/gcc/testsuite/gcc/pr51447.x2/test/gnu/ 
gcc/gcc/gcc/testsuite/gcc.c-torture/execute/pr51447.c: In function  
'main':/test/gnu/gcc/gcc/gcc/testsuite/gcc.c-torture/execute/pr51447.c: 
27:1: internal c
ompiler error: in mark_jump_label_1, at jump.c:11340x40000000005c98cf  
mark_jump_label_1        ../../gcc/gcc/jump.c:1134
0x40000000005c95df mark_jump_label_1        ../../gcc/gcc/jump.c:1194
0x40000000005c9347 mark_jump_label(rtx_def*, rtx_def*,  
int)        ../../gcc/gcc/jump.c:1061
0x40000000005c9b87 mark_all_labels
         ../../gcc/gcc/jump.c:303
0x40000000005c9b87 rebuild_jump_labels_1
         ../../gcc/gcc/jump.c:83
0x40000000005c9fb3 rebuild_jump_labels(rtx_def*)
         ../../gcc/gcc/jump.c:103
0x4000000000370177 cfg_layout_finalize()
         ../../gcc/gcc/cfgrtl.c:3805
0x4000000000a4d42f rest_of_handle_reorder_blocks
         ../../gcc/gcc/bb-reorder.c:2225
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See <http://gcc.gnu.org/bugs.html> for instructions.
compiler exited with status 1

Possibly, the addresses could be truncated modulo 4.

Adding libbacktrace support to 32-bit PA HP-UX (SOM) looks to be a much
tougher.  In addition, there is no equivalent to dlgetname.  On HP-UX  
11.11
and later, it is possible to get a path to the executable using the  
pstat interface.
On earlier systems, a file system walk can be done but it is too  
slow.  Think
it would be better to use argv[0] with some additional checks.

Dave
--
John David Anglin    dave.anglin@bell.net

[Bug bootstrap/54926] [4.8 Regression] Bootstrap comparison failure for various files in libbacktrace

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54926

--- Comment #10 from Jakub Jelinek <jakub at gcc dot gnu.org> 2012-12-07 14:14:33 UTC ---
Author: jakub
Date: Fri Dec  7 14:14:25 2012
New Revision: 194303

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=194303
Log:
    PR bootstrap/54926
    * Makefile.am (AM_CFLAGS): Add -frandom-seed=$@.
    * Makefile.in: Regenerated.

Modified:
    trunk/libbacktrace/ChangeLog
    trunk/libbacktrace/Makefile.am
    trunk/libbacktrace/Makefile.in

[Bug bootstrap/54926] [4.8 Regression] Bootstrap comparison failure for various files in libbacktrace

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54926

--- Comment #11 from Jakub Jelinek <jakub at gcc dot gnu.org> 2012-12-07 14:19:31 UTC ---
Please post patches to gcc-patches.

[Bug bootstrap/54926] [4.8 Regression] Bootstrap comparison failure for various files in libbacktrace

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54926

--- Comment #12 from Jakub Jelinek <jakub at gcc dot gnu.org> 2012-12-11 11:41:04 UTC ---
Created attachment 28926
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=28926
gcc48-pr54926.patch

Richard discovered that adding it unconditionally doesn't work with system
compilers, either too old g++'s or perhaps other vendor compilers.
Untested fix attached.

[Bug bootstrap/54926] [4.8 Regression] Bootstrap comparison failure for various files in libbacktrace

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54926

--- Comment #13 from Jakub Jelinek <jakub at gcc dot gnu.org> 2012-12-11 18:45:52 UTC ---
Author: jakub
Date: Tue Dec 11 18:45:45 2012
New Revision: 194412

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=194412
Log:
    PR bootstrap/54926
    * Makefile.am (AM_CFLAGS): Remove -frandom-seed=$@.
    * configure.ac: If --with-target-subdir, add -frandom-seed=$@
    to EXTRA_FLAGS unconditionally, otherwise check whether the compiler
    accepts it.
    * Makefile.in: Regenerated.
    * configure: Regenerated.

Modified:
    trunk/libbacktrace/ChangeLog
    trunk/libbacktrace/Makefile.am
    trunk/libbacktrace/Makefile.in
    trunk/libbacktrace/configure
    trunk/libbacktrace/configure.ac

[Bug bootstrap/54926] [4.8 Regression] Bootstrap comparison failure for various files in libbacktrace

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54926

Richard Biener <rguenth at gcc dot gnu.org> changed:

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

--- Comment #14 from Richard Biener <rguenth at gcc dot gnu.org> 2012-12-21 12:15:14 UTC ---
I suppose the bootstrap miscompare is fixed.