[Bug libstdc++/56002] New: [mutex] allow generic classes to be used without requiring plattform support for threads

[Bug libstdc++/56002] New: [mutex] allow generic classes to be used without requiring plattform support for threads

[npl at chello dot at]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56002

             Bug #: 56002
           Summary: [mutex] allow generic classes to be used without
                    requiring plattform support for threads
    Classification: Unclassified
           Product: gcc
           Version: 4.7.2
            Status: UNCONFIRMED
          Severity: enhancement
          Priority: P3
         Component: libstdc++
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: npl@chello.at


Created attachment 29179
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=29179
patch for mutex. diffed against 4.7.2

I am using gcc & libstdc++ on a plattform that isnt natively supported and thus
thread-functionality is not available from libstdc++.
However I would like to be able to still use std::lock_guard, std::unique_lock,
std::lock with my own mutex-classes. There ist no technical reason to prevent
use of those generic classes and functions which are deliberately designed to
work with custom implementations.

---mutex like it is now (all-or-nothing):

#if HAS_GCC_THREADS
<mutexes definiton>

<generic stuff like defer_lock_t,lock_guard, unique_lock, lock>

<once_flag>
#endif
----------------------------------------

---mutex like it should be:
#if HAS_GCC_THREADS
<mutexes definiton>
#endif

<generic stuff like defer_lock_t,lock_guard, unique_lock, lock>

#if HAS_GCC_THREADS
<once_flag>
#endif
----------------------------------------

[Bug libstdc++/56002] [mutex] allow generic classes to be used without requiring plattform support for threads

[redi at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56002

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2013-01-16
     Ever Confirmed|0                           |1

[Bug libstdc++/56002] [C++11] allow generic locks to be used without requiring plattform support for threads

[daniel.kruegler at googlemail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56002

Daniel Krügler <daniel.kruegler at googlemail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |daniel.kruegler at
                   |                            |googlemail dot com

--- Comment #1 from Daniel Krügler <daniel.kruegler at googlemail dot com> 2013-01-17 15:06:50 UTC ---
I agree. Today I needed to duplicate std::lock_guard because of this problem

[Bug libstdc++/56002] [C++11] allow generic locks to be used without requiring plattform support for threads

[redi at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56002

--- Comment #2 from Jonathan Wakely <redi at gcc dot gnu.org> 2013-01-17 16:19:19 UTC ---
Yep, I'm fixing it.

I went to add a test for locks that wouldn't rely on thread support and found
I'd already added one ages ago:
http://gcc.gnu.org/viewcvs/trunk/libstdc%2B%2B-v3/testsuite/30_threads/lock_guard/cons/1.cc?revision=185390&content-type=text%2Fplain&view=co

That just needs the dejagnu target selectors removed so it always runs.

[Bug libstdc++/56002] [C++11] allow generic locks to be used without requiring plattform support for threads

[npl at chello dot at]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56002

--- Comment #3 from npl at chello dot at 2013-01-17 20:43:35 UTC ---
great, response looks already more promising than my other gcc
patches/requests.
Any chance this will find its way into 4.7.3?

[Bug libstdc++/56002] [C++11] allow generic locks to be used without requiring plattform support for threads

[redi at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56002

--- Comment #4 from Jonathan Wakely <redi at gcc dot gnu.org> 2013-03-16 19:46:07 UTC ---
Author: redi
Date: Sat Mar 16 19:45:53 2013
New Revision: 196706

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=196706
Log:
    PR libstdc++/56002
    * include/std/mutex (lock_guard, unique_lock, lock): Define without
    depending on _GLIBCXX_HAS_GTHREADS.
    * testsuite/30_threads/lock_guard/cons/1.cc: Run on all targets.

Modified:
    trunk/libstdc++-v3/ChangeLog
    trunk/libstdc++-v3/include/std/mutex
    trunk/libstdc++-v3/testsuite/30_threads/lock_guard/cons/1.cc

[Bug libstdc++/56002] [C++11] allow generic locks to be used without requiring plattform support for threads

[redi at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56002

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |ASSIGNED
         AssignedTo|unassigned at gcc dot       |redi at gcc dot gnu.org
                   |gnu.org                     |
   Target Milestone|---                         |4.7.3

--- Comment #5 from Jonathan Wakely <redi at gcc dot gnu.org> 2013-03-16 19:52:42 UTC ---
Fixed on trunk so far, the fix will also be done for 4.7.3 and 4.8.1

[Bug libstdc++/56002] [C++11] allow generic locks to be used without requiring plattform support for threads

[redi at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56002

--- Comment #6 from Jonathan Wakely <redi at gcc dot gnu.org> 2013-03-16 20:22:40 UTC ---
Author: redi
Date: Sat Mar 16 20:22:30 2013
New Revision: 196710

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=196710
Log:
    PR libstdc++/56002
    * include/std/mutex (lock_guard, unique_lock, lock): Define without
    depending on _GLIBCXX_HAS_GTHREADS.
    * testsuite/30_threads/lock_guard/cons/1.cc: Run on all targets.

Modified:
    branches/gcc-4_7-branch/libstdc++-v3/ChangeLog
    branches/gcc-4_7-branch/libstdc++-v3/include/std/mutex
   
branches/gcc-4_7-branch/libstdc++-v3/testsuite/30_threads/lock_guard/cons/1.cc

[Bug libstdc++/56002] [C++11] allow generic locks to be used without requiring plattform support for threads

[redi at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56002

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

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

--- Comment #7 from Jonathan Wakely <redi at gcc dot gnu.org> 2013-03-24 17:51:52 UTC ---
Fixed for 4.8.1 by this patch:

Author: redi
Date: Sun Mar 24 17:50:44 2013
New Revision: 197020

URL: http://gcc.gnu.org/viewcvs?rev=197020&root=gcc&view=rev
Log:
    PR libstdc++/56002
    * include/std/mutex (lock_guard, unique_lock, lock): Define without
    depending on _GLIBCXX_HAS_GTHREADS.
    * testsuite/30_threads/lock_guard/cons/1.cc: Run on all targets.

Modified:
    branches/gcc-4_8-branch/libstdc++-v3/ChangeLog
    branches/gcc-4_8-branch/libstdc++-v3/include/std/mutex
   
branches/gcc-4_8-branch/libstdc++-v3/testsuite/30_threads/lock_guard/cons/1.cc