Re: [Boost-users] problems with Boost.Thread on VS10

Subject: Re: [Boost-users] problems with Boost.Thread on VS10
From: Vicente J. Botet Escriba (vicente.botet_at_[hidden])
Date: 2012-04-09 13:41:05

Le 08/04/12 17:18, Jeffrey Lee Hellrung, Jr. a écrit :
> On Sun, Apr 8, 2012 at 5:46 AM, Vicente J. Botet Escriba 
> <vicente.botet_at_[hidden] <mailto:vicente.botet_at_[hidden]>> wrote:
>
>     Le 07/04/12 11:11, John M. Dlugosz a écrit :
>
>         On 4/6/2012 11:59 AM, Vicente J. Botet Escriba wrote:
>
>             As you are using std::move, &&, ... why not using directly
>             the C++11 Thread library
>             provided with the compiler?
>
>
>         1) VS10 has && and std::move, but does not have the C++11
>         threading library.
>          1b) A naive implementation (just starts a new OS thread) is
>         not wanted.
>          1c) but, an overly heavy implementation is not wanted either
>         (i.e VS11 beta), because of additional dependencies in the
>         program to distribute.
>         2) In the final code, the && will be optional, to avoid copies
>         on compilers that support it, but must work with compilers
>         that don't.
>         3) I need to preserve semantics of the code I'm replacing with
>         modern C++ forms.
>
>     OK, I see.
>
>
>
>             BTW, Boost.Thread could not implement async using Boost,
>             as Boost.Tuple, Boost.Bind
>             Boost.Fusion (Tuple) because these libraries dont manage
>             with rvalue references.
>
>
>         I don't understand how that applies to my compiler problem.
>          It's telling me that
>
>                   task_object(F const& f_);   // << refers to look here
>                   task_object(F&& f_);         // <<<< Error here
>
>         are not a valid overloading set and instead conflict.
>
>     Sorry, I misunderstood your message.
>
>     After applying the following patch your example compiles. Please
>     could you try it?
>
>     Could you also add a Trac ticket so that this is tracked?
>
>     HTH,
>     Vicente
>
>
> Vicente,
>
> It looks like you're just removing the task_object::task_object(F 
> const &) overload. Seems strange that this overload existed but was/is 
> never actually suppose to be used. ...except when F is a function 
> pointer, I guess???
>
> I sent a message to the list recently observing that one problem was 
> the binding of F to be an lvalue reference (according to the error 
> message, AFAICS), meaning that "F const &" and "F&&" are exactly the 
> same type. Perhaps this behavior should be addressed directly?
>
>
>
After the commit some error have appeared on the regression test (see 
below). It seems that the rvalue reference semantic has changed a lot 
for gcc. I will try to use the last design for this compiler version. 
Then I'll see what needs to be done for other compilers as soon as 
results appear on the regression tests page.

Best,
Vicente

Test output: Sandia-gcc-4.3.4_0x - thread - test_4521 / gcc-4.3.4_0x
Rev 77845 / Mon, 9 Apr 2012 05:37:45 +0000
*Report Time: *Mon, 9 Apr 2012 15:38:34 +0000
Compile [2012-04-09 06:09:04 UTC]: fail

     "/sierra/Sntools/extras/compilers/gcc-4.3.4/bin/g++"  -ftemplate-depth-128 -std=gnu++0x -O0 -fno-inline -Wall -pedantic -g -pthread -fPIC -Wextra -Wno-long-long -pedantic -DBOOST_ALL_NO_LIB=1 -DBOOST_CHRONO_DYN_LINK=1 -DBOOST_SYSTEM_DYN_LINK=1 -DBOOST_SYSTEM_NO_DEPRECATED -DBOOST_THREAD_BUILD_DLL=1 -DBOOST_THREAD_POSIX -DBOOST_THREAD_USE_DLL=1  -I".." -c -o "/scratch/kbelco/boost/results/boost/bin.v2/libs/thread/test/test_4521.test/gcc-4.3.4_0x/debug/threading-multi/test_4521.o" "../libs/thread/test/test_4521.cpp"

../boost/thread/future.hpp: In constructor ???boost::packaged_task<R>::packaged_task(R (*)()) [with R = int]???:
../libs/thread/test/test_4521.cpp:9:   instantiated from here
../boost/thread/future.hpp:1830: error: call of overloaded ???task_object(int (*&)())??? is ambiguous
../boost/thread/future.hpp:1705: note: candidates are: boost::detail::task_object<R, F>::task_object(F&&) [with R = int, F = int (*)()]
../boost/thread/future.hpp:1699: note:                 boost::detail::task_object<R, F>::task_object(R (*)()) [with R = int, F = int (*)()]
../boost/thread/future.hpp:1696: note:                 boost::detail::task_object<int, int (*)()>::task_object(const boost::detail::task_object<int, int (*)()>&)

Test output: Sandia-gcc-4.4.4_0x - thread - test_futures / gcc-4.4.4_0x
Rev 77847 / Mon, 9 Apr 2012 08:48:03 +0000
*Report Time: *Mon, 9 Apr 2012 15:38:34 +0000
Compile [2012-04-09 11:24:07 UTC]: fail

     "/sierra/Sntools/extras/compilers/gcc-4.4.4/bin/g++"  -ftemplate-depth-128 -std=gnu++0x -O0 -fno-inline -Wall -pedantic -g -pthread -fPIC -Wextra -Wno-long-long -pedantic -DBOOST_ALL_NO_LIB=1 -DBOOST_CHRONO_DYN_LINK=1 -DBOOST_SYSTEM_DYN_LINK=1 -DBOOST_SYSTEM_NO_DEPRECATED -DBOOST_TEST_NO_AUTO_LINK=1 -DBOOST_THREAD_BUILD_DLL=1 -DBOOST_THREAD_POSIX -DBOOST_THREAD_USE_DLL=1  -I".." -c -o "/scratch/kbelco/boost/results/boost/bin.v2/libs/thread/test/test_futures.test/gcc-4.4.4_0x/debug/threading-multi/test_futures.o" "../libs/thread/test/test_futures.cpp"

In file included from ../libs/thread/test/test_futures.cpp:10:
../boost/thread/future.hpp: In constructor ???boost::packaged_task<R>::packaged_task(R (*)()) [with R = int]???:
../libs/thread/test/test_futures.cpp:247:   instantiated from here
../boost/thread/future.hpp:1830: error: call of overloaded ???task_object(int (*&)())??? is ambiguous
../boost/thread/future.hpp:1705: note: candidates are: boost::detail::task_object<R, F>::task_object(F&&) [with R = int, F = int (*)()]
../boost/thread/future.hpp:1699: note:                 boost::detail::task_object<R, F>::task_object(R (*)()) [with R = int, F = int (*)()]
../boost/thread/future.hpp:1696: note:                 boost::detail::task_object<int, int (*)()>::task_object(const boost::detail::task_object<int, int (*)()>&)
../boost/thread/future.hpp: In constructor ???boost::packaged_task<R>::packaged_task(R (*)()) [with R = void]???:
../libs/thread/test/test_futures.cpp:362:   instantiated from here
../boost/thread/future.hpp:1830: error: call of overloaded ???task_object(void (*&)())??? is ambiguous
../boost/thread/future.hpp:1759: note: candidates are: boost::detail::task_object<void, F>::task_object(F&&) [with F = void (*)()]
../boost/thread/future.hpp:1753: note:                 boost::detail::task_object<void, F>::task_object(void (*)()) [with F = void (*)()]
../boost/thread/future.hpp:1696: note:                 boost::detail::task_object<void, void (*)()>::task_object(const boost::detail::task_object<void, void (*)()>&)
../boost/thread/future.hpp: In constructor ???boost::packaged_task<R>::packaged_task(R (*)()) [with R = int&]???:
../libs/thread/test/test_futures.cpp:382:   instantiated from here
../boost/thread/future.hpp:1830: error: call of overloaded ???task_object(int&  (*&)())??? is ambiguous
../boost/thread/future.hpp:1705: note: candidates are: boost::detail::task_object<R, F>::task_object(F&&) [with R = int&, F = int&  (*)()]
../boost/thread/future.hpp:1699: note:                 boost::detail::task_object<R, F>::task_object(R (*)()) [with R = int&, F = int&  (*)()]
../boost/thread/future.hpp:1696: note:                 boost::detail::task_object<int&, int&  (*)()>::task_object(const boost::detail::task_object<int&, int&  (*)()>&)