[Bug libstdc++/57440] Memory usage with future and std containers
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57440 --- Comment #2 from DrD --- (In reply to Jonathan Wakely from comment #1) > (In reply to DrD from comment #0) > > // ... launch the threads > > vector > values; > > for (uint w=0; w > values.push_back(std::async(TestFutures)); > > } > > One quick comment, without analysing the issue: > > No threads are launched in your program. Currently GCC's std::async always > behaves as std::async(std::launch::deferred, ...) so to run in a new thread > you need to explicitly call std::async(std::launch::async, TestFutures) Oh! thank you very much for the tip!
[Bug libstdc++/57440] Memory usage with future and std containers
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57440 --- Comment #5 from DrD --- (In reply to Jonathan Wakely from comment #3) > Also I can't reproduce this on GNU/Linux, the memory usage is bounded as > expected. > > I'm surprised this even compiles with Mingw, are you using Mingw-w64 with > libpthread-win32? Since it seems to be platform-specific it could be a > resource leak of mutexes or condition variables, so my wild guess is that > libpthread-win32 requires pthread_mutex_destroy or pthread_cond_destroy to > be used. > > Does it make any difference if you add these to the very top of the source > file, before including any headers? > > #define _GTHREAD_USE_MUTEX_INIT_FUNC > #define _GTHREAD_USE_COND_INIT_FUNC It does compile in MinGw. Unfortunately the two #define lines don't help either. I forgot to mention that I had already been warned that the test code works OK in Linux, see: http://stackoverflow.com/questions/16489389/memory-usage-with-future-and-containers-in-qt-mingw
[Bug libstdc++/57440] Memory usage with future and std containers
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57440
--- Comment #6 from DrD ---
(In reply to Jonathan Wakely from comment #4)
> If my guess is right you should be able to reproduce the unbounded memory
> usage with this:
>
> #include
>
> int f() { return 0; }
>
> int main()
> {
> for (int i=0; i < 10; ++i)
> std::async(f).get();
> }
>
>
> And you should not see it happen with this:
>
> #define _GTHREAD_USE_MUTEX_INIT_FUNC
> #define _GTHREAD_USE_COND_INIT_FUNC
>
> #include
>
> int f() { return 0; }
>
> int main()
> {
> for (int i=0; i < 10; ++i)
> std::async(f).get();
> }
>
> Please check and update the bug report, thanks.
Hi Jonathan,
Thanks for your help. I just tried this code and the memory problem is there
with and without the #define lines.
I haven't managed to get this bug tested on Windows by anyone else yet. I have
tried in two different computers, though (not enough, I think).
Any suggestions?
[Bug libstdc++/57440] Memory usage with future and std containers
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57440 --- Comment #8 from DrD --- (In reply to Jonathan Wakely from comment #7) > You didn't answer the question about which mingw compiler you are using, the > standard mingw gcc does not support std::async. >From my first post: "I compile it with gcc 4.7.2 (MinGW 4.7.2) in Qt 5.0.1, Qt Creator 2.6.2." Is that what you need or are you after some other detail I have omitted?
[Bug libstdc++/57440] Memory usage with future and std containers
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57440 --- Comment #10 from DrD --- (In reply to Jonathan Wakely from comment #7) > You didn't answer the question about which mingw compiler you are using, the > standard mingw gcc does not support std::async. >From my first post: "I compile it with gcc 4.7.2 (MinGW 4.7.2) in Qt 5.0.1, Qt Creator 2.6.2." Is that what you need or are you after some other detail I have omitted?(In reply to Jonathan Wakely from comment #9) > Some other detail. I don't care about Qt Creator, it's not a compiler, and > the version of Qt is compeltely irrelevant because you're not using Qt. > > I don't believe you can be using Mingw 4.7.2, because that doesn't support > std::async(). What does 'gcc -v' show? I am using the MinGW copy that comes with Qt. If I go to the bin folder I obtain: C:\Qt\Qt5.0.1\Tools\MinGW\bin>gcc -v Using built-in specs. COLLECT_GCC=gcc COLLECT_LTO_WRAPPER=c:/qt/qt5.0.1/tools/mingw/bin/../libexec/gcc/i686-w64-mingw32/4.7.2/lto-wrapper.exe Target: i686-w64-mingw32 Configured with: ../../../src/gcc-4.7.2/configure --host=i686-w64-mingw32 --build=i686-w64-mingw32 --target=i686-w64-mingw32 --prefix=/temp/x32-4.7.2-posix-sjlj-r8/prefix --with-sysroot=/temp/x32-4.7.2-posix-sj lj-r8/prefix --enable-shared --enable-static --enable-targets=all --enable-multilib --enable-languages=c,c++,fortran,lto --enable-libstdcxx-time=yes --enable-threads=posix --enable-libgomp --enable-lto --enable -graphite --enable-cloog-backend=isl --enable-checking=release --enable-fully-dynamic-string --enable-version-specific-runtime-libs --enable-sjlj-exceptions --disable-ppl-version-check --disable-cloog-version-c heck --disable-libstdcxx-pch --disable-libstdcxx-debug --disable-bootstrap --disable-rpath --disable-win32-registry --disable-nls --disable-werror --disable-symvers --with-gnu-as --with-gnu-ld --with-arch-32=i6 86 --with-arch-64=nocona --with-tune-32=core2 --with-tune-64=core2 --with-host-libstdcxx='-static -lstdc++' --with-libiconv --with-system-zlib --with-gmp=/temp/mingw-prereq/i686-w64-mingw32-static --with-mpfr=/ temp/mingw-prereq/i686-w64-mingw32-static --with-mpc=/temp/mingw-prereq/i686-w64-mingw32-static --with-ppl=/temp/mingw-prereq/i686-w64-mingw32-static --with-cloog=/temp/mingw-prereq/i686-w64-mingw32-static --wi th-pkgversion='Built by MinGW-builds project' --with-bugurl=http://sourceforge.net/projects/mingwbuilds/ CFLAGS='-O2 -pipe -fomit-frame-pointer -I/temp/x32-4.7.2-posix-sjlj-r8/libs/include -I/temp/mingw-prereq/ x32-zlib/include -I/temp/mingw-prereq/i686-w64-mingw32-static/include' CXXFLAGS='-O2 -pipe -fomit-frame-pointer -I/temp/x32-4.7.2-posix-sjlj-r8/libs/include -I/temp/mingw-prereq/x32-zlib/include -I/temp/mingw-p rereq/i686-w64-mingw32-static/include' CPPFLAGS= LDFLAGS='-pipe -L/temp/x32-4.7.2-posix-sjlj-r8/libs/lib -L/temp/mingw-prereq/x32-zlib/lib -L/temp/mingw-prereq/i686-w64-mingw32-static/lib -L/temp/x32-4.7.2-posi x-sjlj-r8/prefix/opt/lib' Thread model: posix gcc version 4.7.2 (Built by MinGW-builds project) I am relatively new to MinGw (it shows), so I am not too familiar with the particularities of Qt's copy.
