[Bug c++/52477] New: Wrong initialization order? __attribute__((constructor)) vs static data access

[Bug c++/52477] New: Wrong initialization order? __attribute__((constructor)) vs static data access

[przemoc at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52477

             Bug #: 52477
           Summary: Wrong initialization order?
                    __attribute__((constructor)) vs static data access
    Classification: Unclassified
           Product: gcc
           Version: 4.7.0
            Status: UNCONFIRMED
          Severity: major
          Priority: P3
         Component: c++
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: przemoc@gmail.com


Created attachment 26821
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=26821
Short exemplary code showing the problem

Attached file compiles flawlessly on 4.7.0, but the output binary segfaults.
Works fine in 4.6.2 though (as expected).

Looks like a serious regression.

g++-4.7 (GCC) 4.7.0 20120304 (prerelease)
built on debian wheezy x64 with:
--enable-languages=c,c++ --prefix=/opt/gcc-4.7 --program-suffix=-4.7

svn+ssh://gcc.gnu.org/svn/gcc/branches/gcc-4_7-branch@184878

[Bug c++/52477] Wrong initialization order? __attribute__((constructor)) vs static data access

[pluto at agmk dot net]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52477

Pawel Sikora <pluto at agmk dot net> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |pluto at agmk dot net

--- Comment #1 from Pawel Sikora <pluto at agmk dot net> 2012-03-04 13:54:09 UTC ---
looks like .init_array vs. .ctors problem.

[Bug c++/52477] Wrong initialization order? __attribute__((constructor)) vs static data access

[pluto at agmk dot net]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52477

--- Comment #2 from Pawel Sikora <pluto at agmk dot net> 2012-03-04 14:16:29 UTC ---
you should specify explicit initialization order to avoid gpf, e.g.:

static std::map<int, int> m __attribute__((init_priority(101)));
static void insert() __attribute__((constructor(102)));

[Bug c++/52477] Wrong initialization order? __attribute__((constructor)) vs static data access

[przemoc at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52477

--- Comment #3 from Przemysław Pawełczyk <przemoc at gmail dot com> 2012-03-04 14:24:10 UTC ---
Thanks for solution, but...

Isn't such order obvious or isn't it at least the most widely used one? I mean
that by default static data initialization should precede
constructor-functions, no? It worked in gcc 4.6 and is there any good reason to
break it?

[Bug c++/52477] Wrong initialization order? __attribute__((constructor)) vs static data access

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52477

--- Comment #4 from Richard Guenther <rguenth at gcc dot gnu.org> 2012-03-05 10:20:37 UTC ---
I think it's undefined what you relied upon.