[CMake] undefined reference to 'pthread_create'

[J Decker]

On Thu, Feb 4, 2016 at 9:55 AM, Aaron Boxer <boxerab at gmail.com> wrote:
> Thanks. So, even though threading is part of the standard, I still need to
> link to pthreads library ?

Yes; sounds more like an issue for GCC :)   I mean you don't have to
tell it to link against c library or c++ runtime libraries... and it
IS pthread specific so it's not like there's going to be some
alternative provider for such services.

using MinGW under linux to get a windows output it links automatically
to a 'winpthreads.dll' which then becomes a runtime requirement... so
it's not impossible for the compiler suite to do.


>
> On Thu, Feb 4, 2016 at 11:53 AM, rpelapur at archlinux.info
> <rpelapur at archlinux.info> wrote:
>>
>> I believe that doesn't have anything to do with C11 flags. You are just
>> missing the link to the pthread library. I could be wrong.
>>
>> Try and add this to your cmake file:
>>
>> find_package (Threads)
>>
>> target_link_libraries (myexecutable/lib ${CMAKE_THREAD_LIBS_INIT})
>>
>>
>>
>> Sent from my iPhone
>>
>> On Feb 4, 2016, at 10:42 AM, Aaron Boxer <boxerab at gmail.com> wrote:
>>
>> Hello,
>> I have a cmake project that uses C++11 threads.
>> I have added the lines
>>
>> set (CMAKE_CXX_STANDARD 14)
>> set(CMAKE_CXX_STANDARD_REQUIRED ON)
>>
>>
>> CMAKE version is 3.2.2, running on Ubuntu.
>>
>> When I try to build, I get the error
>>
>> undefined reference to `pthread_create`
>>
>> Any ideas on how to fix this?
>>
>> Thanks!
>> Aaron
>>
>> --
>>
>> Powered by www.kitware.com
>>
>> Please keep messages on-topic and check the CMake FAQ at:
>> http://www.cmake.org/Wiki/CMake_FAQ
>>
>> Kitware offers various services to support the CMake community. For more
>> information on each offering, please visit:
>>
>> CMake Support: http://cmake.org/cmake/help/support.html
>> CMake Consulting: http://cmake.org/cmake/help/consulting.html
>> CMake Training Courses: http://cmake.org/cmake/help/training.html
>>
>> Visit other Kitware open-source projects at
>> http://www.kitware.com/opensource/opensource.html
>>
>> Follow this link to subscribe/unsubscribe:
>> http://public.kitware.com/mailman/listinfo/cmake
>
>
>
> --
>
> Powered by www.kitware.com
>
> Please keep messages on-topic and check the CMake FAQ at:
> http://www.cmake.org/Wiki/CMake_FAQ
>
> Kitware offers various services to support the CMake community. For more
> information on each offering, please visit:
>
> CMake Support: http://cmake.org/cmake/help/support.html
> CMake Consulting: http://cmake.org/cmake/help/consulting.html
> CMake Training Courses: http://cmake.org/cmake/help/training.html
>
> Visit other Kitware open-source projects at
> http://www.kitware.com/opensource/opensource.html
>
> Follow this link to subscribe/unsubscribe:
> http://public.kitware.com/mailman/listinfo/cmake