[Bug libstdc++/49322] New: [4.7 Regression] Many libstdc++ testsuite failures

[Bug libstdc++/49322] New: [4.7 Regression] Many libstdc++ testsuite failures

[hjl.tools at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49322

           Summary: [4.7 Regression] Many libstdc++ testsuite failures
           Product: gcc
           Version: 4.7.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: libstdc++
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: hjl.tools@gmail.com


On Linux/ia32, revision 174772 gave

FAIL: 20_util/is_copy_assignable/value.cc (test for excess errors)
FAIL: 20_util/is_move_assignable/value.cc (test for excess errors)
FAIL: 20_util/is_nothrow_move_assignable/value.cc (test for excess errors)
FAIL: 23_containers/map/modifiers/insert/2.cc (test for excess errors)
FAIL: 23_containers/map/modifiers/insert/3.cc (test for excess errors)
FAIL: 23_containers/multimap/modifiers/insert/4.cc (test for excess errors)

Revision 174765 is OK.

[Bug libstdc++/49322] [4.7 Regression] Many libstdc++ testsuite failures

[hjl.tools at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49322

H.J. Lu <hjl.tools at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |jason at redhat dot com

--- Comment #1 from H.J. Lu <hjl.tools at gmail dot com> 2011-06-08 00:38:42 UTC ---
It is caused by one of revision 174770/174771/174772.

[Bug c++/49322] [4.7 Regression] Many libstdc++ testsuite failures

[jason at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49322

Jason Merrill <jason at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |ASSIGNED
   Last reconfirmed|                            |2011.06.08 02:43:27
                 CC|                            |jason at gcc dot gnu.org
          Component|libstdc++                   |c++
         AssignedTo|unassigned at gcc dot       |jason at gcc dot gnu.org
                   |gnu.org                     |
     Ever Confirmed|0                           |1

[Bug c++/49322] [4.7 Regression] Many libstdc++ testsuite failures

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49322

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |4.7.0

[Bug c++/49322] [4.7 Regression] Many libstdc++ testsuite failures

[dominiq at lps dot ens.fr]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49322

--- Comment #2 from Dominique d'Humieres <dominiq at lps dot ens.fr> 2011-06-08 11:47:36 UTC ---
On x86_64-apple-darwin10 at revision 174779 I only see

FAIL: 20_util/is_move_assignable/value.cc (test for excess errors)
WARNING: 20_util/is_move_assignable/value.cc compilation failed to produce
executable

The error is

FAIL: 20_util/is_move_assignable/value.cc (test for excess errors)
Excess errors:
/opt/gcc/work/libstdc++-v3/testsuite/20_util/is_move_assignable/value.cc:60:1:
internal compiler error: tree check: expected tree that contains 'common'
structure, have '' in gt_ggc_mx_lang_tree_node, at ./gt-cp-tree.h:147

[Bug c++/49322] [4.7 Regression] Many libstdc++ testsuite failures

[dominiq at lps dot ens.fr]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49322

--- Comment #3 from Dominique d'Humieres <dominiq at lps dot ens.fr> 2011-06-08 12:31:20 UTC ---
I have forgotten to say that I see the failure with -m64 only.

[Bug c++/49322] [4.7 Regression] Many libstdc++ testsuite failures

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49322

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

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

--- Comment #4 from Jakub Jelinek <jakub at gcc dot gnu.org> 2011-06-08 12:45:07 UTC ---
Indeed, this is caused by
http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=174772
deduction_tsubst_fntype is called, creates a TREE_LIST, pushes it using
push_tinst_level, then during tsubst call (much deeper in the backtrace fact)
add_pending_template is called, which sticks pointer to current_tinst_level
(whose chain goes back to struct tinst_level that points to the TREE_LIST
from deduction_tsubst_fntype), then some pop_tinst_level calls are called
and finally tsubst returns to deduction_tsubst_fntype, which calls
pop_tinst_level (but, all those pop_tinst_level calls just tweak
current_tinst_level, they don't change what add_pending_template remembered)
and then ggc_frees the TREE_LIST, which means that during GC
pending_templates(->next)*->tinst(->next)*->decl suddenly points to
freed memory and thus crashes.
Either it shouldn't be freed, or before calling pop_tinst_level it should be
reset to NULL or something similar (current_tinst_level->decl = NULL;
pop_tinst_level (); ggc_free (tinst); ?), or it is wrong that
add_pending_template has been called or remembered that.

[Bug c++/49322] [4.7 Regression] Many libstdc++ testsuite failures

[jason at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49322

Jason Merrill <jason at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|                            |FIXED
   Target Milestone|4.7.0                       |---

--- Comment #5 from Jason Merrill <jason at gcc dot gnu.org> 2011-06-10 12:52:36 UTC ---
Fixed.