[Bug c++/60702] New: thread_local initialization

[Bug c++/60702] New: thread_local initialization

[dv.main at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60702

            Bug ID: 60702
           Summary: thread_local initialization
           Product: gcc
           Version: 4.8.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: dv.main at gmail dot com

Created attachment 32480
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=32480&action=edit
Gcc verbose output

Invalid thread local object initialization.
Snippet:

#include <iostream>

using namespace std;

struct far {
    struct boo {
        boo () {
            cerr << "bar::boo" << endl;
        }
        int i = 42;
    };

    static void baz() {
        cerr << far::FOO.i << endl;
    }

    static thread_local boo FOO;
};

thread_local typename far::boo far::FOO;

int main() {
    far f;
    cerr << f.FOO.i << endl;
    cerr << far::FOO.i << endl;
    return 0;
}

Output:
0
bar::boo
42

[Bug c++/60702] thread_local initialization

[dv.main at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60702

--- Comment #1 from Stan Pavlovski <dv.main at gmail dot com> ---
Created attachment 32481
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=32481&action=edit
Gcc temp output

[Bug c++/60702] thread_local initialization

[dv.main at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60702

--- Comment #2 from Stan Pavlovski <dv.main at gmail dot com> ---
Created attachment 32482
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=32482&action=edit
Source file

[Bug c++/60702] thread_local initialization

[dv.main at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60702

--- Comment #3 from Stan Pavlovski <dv.main at gmail dot com> ---
Template class' thread_local member is not initialized unless other
non-template class' thread_local member is initialized first:

#include <iostream>

using namespace std;

struct far {
    struct boo {
        boo () {
            cerr << "far::boo" << endl;
        }
        int i = 42;
    };

    static void baz() {
        cerr << far::FOO.i << endl;
    }

    static thread_local boo FOO;
};

template<class T>
struct bar {
    struct foo {
        foo () {
            cerr << "bar::foo" << endl;
        }
        int i = 42;
    };

    void baz() {
        cerr << bar::FOO.i << endl;
    }

    static thread_local foo FOO;
};

template<class T> thread_local typename bar<T>::foo bar<T>::FOO;
thread_local typename far::boo far::FOO;

int main() {
    bar<int> b;
    b.baz();

    far f;
    f.baz();
    return 0;
}

Output:

0
far::boo
bar::foo
42

[Bug c++/60702] thread_local initialization

[arturomdn at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60702

arturomdn at gmail dot com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |arturomdn at gmail dot com

--- Comment #4 from arturomdn at gmail dot com ---
Created attachment 32528
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=32528&action=edit
Smaller testcase that reproduces the problem

clang had the same problem, this smaller test was submitted to the clang team
and they identified it as a duplicate of a recently fixed bug:

http://llvm.org/bugs/show_bug.cgi?id=19254

Which was fixed as follows

http://llvm.org/viewvc/llvm-project?view=revision&revision=204869

With the following comment:

PR19254: If a thread_local data member of a class is accessed via member access
syntax, don't forget to run its initializer.

[Bug c++/60702] thread_local initialization

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=60702

Jonathan Wakely <redi at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |tobias.bruell at gmail dot com

--- Comment #25 from Jonathan Wakely <redi at gcc dot gnu.org> ---
*** Bug 88292 has been marked as a duplicate of this bug. ***

[Bug c++/60702] thread_local initialization

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=60702

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |michael at ensslin dot cc

--- Comment #26 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
*** Bug 60673 has been marked as a duplicate of this bug. ***