[Bug bootstrap/46474] New: [4.6 regression] powerpc64-linux bootstrap comparison failure in libcpp/symtab.o

[Bug bootstrap/46474] New: [4.6 regression] powerpc64-linux bootstrap comparison failure in libcpp/symtab.o

[mikpe at it dot uu.se]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46474

           Summary: [4.6 regression] powerpc64-linux bootstrap comparison
                    failure in libcpp/symtab.o
           Product: gcc
           Version: 4.6.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: bootstrap
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: mikpe@it.uu.se


gcc-4.6-20101113 (r166720) fails to bootstrap on powerpc64-linux:

Comparing stages 2 and 3
warning: gcc/cc1obj-checksum.o differs
warning: gcc/cc1objplus-checksum.o differs
warning: gcc/cc1-checksum.o differs
warning: gcc/cc1plus-checksum.o differs
Bootstrap comparison failure!
libcpp/symtab.o differs
make[2]: *** [compare] Error 1
make[2]: Leaving directory `/mnt/scratch/objdir46'
make[1]: *** [stage3-bubble] Error 2
make[1]: Leaving directory `/mnt/scratch/objdir46'
make: *** [bootstrap] Error 2

The previous weekly snapshot (20101106) bootstrapped w/o problems.

Configured as:
/mnt/scratch/gcc-4.6-20101113/configure
--with-gmp=/home/mikpe/pkgs/linux-ppc64/gmp-4.3.2
--with-mpfr=/home/mikpe/pkgs/linux-ppc64/mpfr-2.4.2
--with-mpc=/home/mikpe/pkgs/linux-ppc64/mpc-0.8.2 --disable-plugin
--disable-lto --disable-nls --enable-multilib --enable-threads=posix
--with-cpu=default32 --enable-checking=release --disable-libmudflap
--enable-languages=c,c++,objc,obj-c++,java,fortran

[Bug bootstrap/46474] [4.6 regression] powerpc64-linux bootstrap comparison failure in libcpp/symtab.o

[dominiq at lps dot ens.fr]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46474

--- Comment #1 from Dominique d'Humieres <dominiq at lps dot ens.fr> 2010-11-14 11:58:51 UTC ---
I also see it on powerpc-apple-darwin9 (r166728, last bootstrap
r166379+patches).

[Bug bootstrap/46474] [4.6 regression] powerpc64-linux bootstrap comparison failure in libcpp/symtab.o

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46474

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |rguenth at gcc dot gnu.org
   Target Milestone|---                         |4.6.0

--- Comment #2 from Richard Guenther <rguenth at gcc dot gnu.org> 2010-11-14 17:41:29 UTC ---
If it's due to the reported difference using fma and not using fma then
probably the tree fma code lacks checks for debug stmts.  Try

Index: tree-ssa-math-opts.c
===================================================================
--- tree-ssa-math-opts.c    (revision 166717)
+++ tree-ssa-math-opts.c    (working copy)
@@ -1534,6 +1534,9 @@

       use_stmt = USE_STMT (use_p);

+      if (is_gimple_debug (use_stmt))
+    continue;
+
       /* For now restrict this operations to single basic blocks.  In theory
      we would want to support sinking the multiplication in
      m = a*b;
@@ -1603,10 +1606,14 @@
   FOR_EACH_IMM_USE_STMT (use_stmt, imm_iter, mul_result)
     {
       gimple_stmt_iterator gsi = gsi_for_stmt (use_stmt);
-      enum tree_code use_code = gimple_assign_rhs_code (use_stmt);
+      enum tree_code use_code;
       tree addop, mulop1, result = mul_result;
       bool negate_p = false;

+      if (is_gimple_debug (use_stmt))
+    continue;
+
+      use_code = gimple_assign_rhs_code (use_stmt);
       if (use_code == NEGATE_EXPR)
     {
       result = gimple_assign_lhs (use_stmt);

[Bug bootstrap/46474] [4.6 regression] powerpc64-linux bootstrap comparison failure in libcpp/symtab.o

[pinskia at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46474

--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> 2010-11-14 17:47:50 UTC ---
(In reply to comment #2)
> If it's due to the reported difference using fma and not using fma then
> probably the tree fma code lacks checks for debug stmts.  Try

If it is due to FMA code, then we have floating point in the gcc code which we
should remove.

[Bug bootstrap/46474] [4.6 regression] powerpc64-linux bootstrap comparison failure in libcpp/symtab.o

[mikpe at it dot uu.se]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46474

--- Comment #4 from Mikael Pettersson <mikpe at it dot uu.se> 2010-11-15 10:14:00 UTC ---
(In reply to comment #2)
> If it's due to the reported difference using fma and not using fma then
> probably the tree fma code lacks checks for debug stmts.  Try

This patch restored bootstrap.  Thanks.

[Bug bootstrap/46474] [4.6 regression] powerpc64-linux bootstrap comparison failure in libcpp/symtab.o

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46474

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |ASSIGNED
   Last reconfirmed|                            |2010.11.15 10:35:28
         AssignedTo|unassigned at gcc dot       |rguenth at gcc dot gnu.org
                   |gnu.org                     |
     Ever Confirmed|0                           |1

--- Comment #5 from Richard Guenther <rguenth at gcc dot gnu.org> 2010-11-15 10:35:28 UTC ---
Mine then.

[Bug bootstrap/46474] [4.6 regression] powerpc64-linux bootstrap comparison failure in libcpp/symtab.o

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46474

--- Comment #6 from Richard Guenther <rguenth at gcc dot gnu.org> 2010-11-15 10:37:15 UTC ---
(In reply to comment #3)
> (In reply to comment #2)
> > If it's due to the reported difference using fma and not using fma then
> > probably the tree fma code lacks checks for debug stmts.  Try
> 
> If it is due to FMA code, then we have floating point in the gcc code which we
> should remove.

libcpp/symtab.c has FP code in ht_dump_statistics.

[Bug bootstrap/46474] [4.6 regression] powerpc64-linux bootstrap comparison failure in libcpp/symtab.o

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46474

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

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

--- Comment #7 from Jakub Jelinek <jakub at gcc dot gnu.org> 2010-11-15 10:48:37 UTC ---
And I'd say it is fine to use floating point there, the dumping doesn't affect
code generation.

[Bug bootstrap/46474] [4.6 regression] powerpc64-linux bootstrap comparison failure in libcpp/symtab.o

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46474

--- Comment #8 from Richard Guenther <rguenth at gcc dot gnu.org> 2010-11-15 12:04:51 UTC ---
Author: rguenth
Date: Mon Nov 15 12:04:46 2010
New Revision: 166750

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=166750
Log:
2010-11-15  Richard Guenther  <rguenther@suse.de>

    PR bootstrap/46474
    * tree-ssa-math-opts.c (convert_mult_to_fma): Disregard debug stmts.

Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/tree-ssa-math-opts.c

[Bug bootstrap/46474] [4.6 regression] powerpc64-linux bootstrap comparison failure in libcpp/symtab.o

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46474

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

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

--- Comment #9 from Richard Guenther <rguenth at gcc dot gnu.org> 2010-11-15 12:05:14 UTC ---
Fixed.

[Bug bootstrap/46474] [4.6 regression] powerpc64-linux bootstrap comparison failure in libcpp/symtab.o

[pinskia at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46474

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |doko at ubuntu dot com

--- Comment #10 from Andrew Pinski <pinskia at gcc dot gnu.org> 2010-11-15 18:36:01 UTC ---
*** Bug 46486 has been marked as a duplicate of this bug. ***