[Bug c/96597] New: valgrind error in do_hoist_insertion during O3 build

[Bug c/96597] New: valgrind error in do_hoist_insertion during O3 build

[dcb314 at hotmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96597

            Bug ID: 96597
           Summary: valgrind error in do_hoist_insertion during O3 build
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
          Assignee: unassigned at gcc dot gnu.org
          Reporter: dcb314 at hotmail dot com
  Target Milestone: ---

==62146== Conditional jump or move depends on uninitialised value(s)
==62146==    at 0xD2A8FD: do_hoist_insertion (tree-ssa-pre.c:3581)
==62146==    by 0xD2A8FD: insert (tree-ssa-pre.c:3685)
==62146==    by 0xD2A8FD: (anonymous namespace)::pass_pre::execute(function*)
(tree-ssa-pre.c:4235)

tree-ssa-pre.c:3581 is

       && PRE_EXPR_REFERENCE (expr)->punned

Configure lines are

../trunk.git/configure --prefix=/home/dcb/gcc/results.20200812.valgrind \
        --disable-bootstrap \
        --disable-multilib \
        --disable-werror \
        --enable-checking=valgrind \
        --enable-languages=c,c++,fortran

sed 's/-O2/-O3/' < Makefile > Makefile.tmp
mv Makefile.tmp Makefile

valgrind is version 3.16.0 and valgrind is configured as follows:

$ more ~/.valgrind*
::::::::::::::
/home/dcb32B/.valgrindrc
::::::::::::::
--suppressions=/home/dcb32B/.valgrind.supp
--expensive-definedness-checks=yes
::::::::::::::
/home/dcb32B/.valgrind.supp
::::::::::::::

{
   bug1
   Memcheck:Cond
   fun:incorporate_penalties
}

[Bug c/96597] valgrind error in do_hoist_insertion during O3 build

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96597

Martin Liška <marxin at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
     Ever confirmed|0                           |1
             Status|UNCONFIRMED                 |WAITING
   Last reconfirmed|                            |2020-08-13
                 CC|                            |marxin at gcc dot gnu.org

--- Comment #1 from Martin Liška <marxin at gcc dot gnu.org> ---
Can you please attached pre-processed source file?

[Bug c/96597] valgrind error in do_hoist_insertion during O3 build

[dcb314 at hotmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96597

--- Comment #2 from David Binderman <dcb314 at hotmail dot com> ---
Created attachment 49055
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=49055&action=edit
gzipped C source code

This attached file is preprocessed from libgcc/libgcov-driver.c.

This line is required to compile it:

/home/dcb/gcc/working/./gcc/xgcc -B/home/dcb/gcc/working/./gcc/
-B/home/dcb/gcc/results.20200812.valgrind/x86_64-pc-linux-gnu/bin/
-B/home/dcb/gcc/results.20200812.valgrind/x86_64-pc-linux-gnu/lib/ -isystem
/home/dcb/gcc/results.20200812.valgrind/x86_64-pc-linux-gnu/include -isystem
/home/dcb/gcc/results.20200812.valgrind/x86_64-pc-linux-gnu/sys-include    -g
-O3 -O2  -g -O3 -DIN_GCC    -W -Wall -Wno-narrowing -Wwrite-strings -Wcast-qual
-Wno-error=format-diag -Wstrict-prototypes -Wmissing-prototypes
-Wno-error=format-diag -Wold-style-definition  -isystem ./include   -fpic
-mlong-double-80 -DUSE_ELF_SYMVER -fcf-protection -mshstk -g -DIN_LIBGCC2
-fbuilding-libgcc -fno-stack-protector   -fpic -mlong-double-80
-DUSE_ELF_SYMVER -fcf-protection -mshstk -I. -I. -I../.././gcc
-I../../../trunk.git/libgcc -I../../../trunk.git/libgcc/.
-I../../../trunk.git/libgcc/../gcc -I../../../trunk.git/libgcc/../include
-I../../../trunk.git/libgcc/config/libbid -DENABLE_DECIMAL_BID_FORMAT
-DHAVE_CC_TLS  -DUSE_TLS -MT _gcov.o -MD -MP -MF _gcov.dep -DL_gcov -c

[Bug c/96597] valgrind error in do_hoist_insertion during O3 build

[dcb314 at hotmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96597

--- Comment #3 from David Binderman <dcb314 at hotmail dot com> ---
Reduced command line:

/home/dcb/gcc/working/./gcc/xgcc -B/home/dcb/gcc/working/./gcc/ -O2 -c

Interestingly, -O3 not required.

I'll have a look at previous versions of gcc then have a go
at reducing the code.

[Bug c/96597] valgrind error in do_hoist_insertion during O3 build

[dcb314 at hotmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96597

--- Comment #4 from David Binderman <dcb314 at hotmail dot com> ---
Code seems ok on date 20200724, so someone has broken something recently.

[Bug c/96597] valgrind error in do_hoist_insertion during O3 build

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96597

Martin Liška <marxin at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|WAITING                     |NEW

--- Comment #5 from Martin Liška <marxin at gcc dot gnu.org> ---
Likely introduced with r11-2545-g1af5cdd77985daf76130f527deac425c43df9f49.

[Bug c/96597] valgrind error in do_hoist_insertion during O3 build

[dcb314 at hotmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96597

--- Comment #6 from David Binderman <dcb314 at hotmail dot com> ---
Created attachment 49056
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=49056&action=edit
C source code

Reduced code attached.

[Bug c/96597] valgrind error in do_hoist_insertion during O3 build

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96597

Martin Liška <marxin at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Assignee|unassigned at gcc dot gnu.org      |marxin at gcc dot gnu.org

--- Comment #7 from Martin Liška <marxin at gcc dot gnu.org> ---
I'm working on that..

[Bug c/96597] valgrind error in do_hoist_insertion during O3 build

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96597

Martin Liška <marxin at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |ASSIGNED

--- Comment #8 from Martin Liška <marxin at gcc dot gnu.org> ---
I've got a fix for it.

[Bug tree-optimization/96597] valgrind error in do_hoist_insertion during O3 build

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96597

Martin Liška <marxin at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |11.0

[Bug tree-optimization/96597] valgrind error in do_hoist_insertion during O3 build

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96597

--- Comment #9 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Martin Liska <marxin@gcc.gnu.org>:

https://gcc.gnu.org/g:adc646b10c7168c3c95373ee9321e3760fc4c5f1

commit r11-2816-gadc646b10c7168c3c95373ee9321e3760fc4c5f1
Author: Martin Liska <mliska@suse.cz>
Date:   Thu Aug 13 13:05:12 2020 +0200

    Add missing vn_reference_t::punned initialization

    gcc/ChangeLog:

            PR tree-optimization/96597
            * tree-ssa-sccvn.c (vn_reference_lookup_call): Add missing
            initialization of ::punned.
            (vn_reference_insert): Use consistently false instead of 0.
            (vn_reference_insert_pieces): Likewise.

[Bug tree-optimization/96597] valgrind error in do_hoist_insertion during O3 build

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96597

Martin Liška <marxin at gcc dot gnu.org> changed:

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

--- Comment #10 from Martin Liška <marxin at gcc dot gnu.org> ---
Fixed.

[Bug tree-optimization/96597] valgrind error in do_hoist_insertion during O3 build

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96597

--- Comment #11 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-10 branch has been updated by Richard Biener
<rguenth@gcc.gnu.org>:

https://gcc.gnu.org/g:c863dec102e0a636b99100639f523d084aafce4e

commit r10-8696-gc863dec102e0a636b99100639f523d084aafce4e
Author: Martin Liska <mliska@suse.cz>
Date:   Thu Aug 13 13:05:12 2020 +0200

    Add missing vn_reference_t::punned initialization

    gcc/ChangeLog:

            PR tree-optimization/96597
            * tree-ssa-sccvn.c (vn_reference_lookup_call): Add missing
            initialization of ::punned.
            (vn_reference_insert): Use consistently false instead of 0.
            (vn_reference_insert_pieces): Likewise.

    (cherry picked from commit adc646b10c7168c3c95373ee9321e3760fc4c5f1)

[Bug tree-optimization/96597] valgrind error in do_hoist_insertion during O3 build

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96597

--- Comment #12 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-9 branch has been updated by Richard Biener
<rguenth@gcc.gnu.org>:

https://gcc.gnu.org/g:f5f932214bf73bbe3334d67a07c632e4fca351f4

commit r9-9538-gf5f932214bf73bbe3334d67a07c632e4fca351f4
Author: Martin Liska <mliska@suse.cz>
Date:   Thu Aug 13 13:05:12 2020 +0200

    Add missing vn_reference_t::punned initialization

    gcc/ChangeLog:

            PR tree-optimization/96597
            * tree-ssa-sccvn.c (vn_reference_lookup_call): Add missing
            initialization of ::punned.
            (vn_reference_insert): Use consistently false instead of 0.
            (vn_reference_insert_pieces): Likewise.