Hi, I built a w64 cross-compiler to make windows binaries on linux. The cross-compiler has Posix threads, not win32 threads. I would like to build boost.thread with it but I have some difficulties: 1. I do not need to link with any library to build applications with C++11 threads but boost build asks for PTW32_INCLUDE and PTW32_LIB otherwise it sets <build>no so that the library is not built. This is easily changed with the following patch: diff -r -u boost_1_64_0-0/libs/thread/build/Jamfile.v2 boost_1_64_0-1/libs/thread/build/Jamfile.v2 --- boost_1_64_0-0/libs/thread/build/Jamfile.v2 2017-04-17 04:22:25.000000000 +0200 +++ boost_1_64_0-1/libs/thread/build/Jamfile.v2 2017-07-12 14:24:03.960979687 +0200 @@ -271,10 +271,6 @@ { result += $(paths) ; } - else - { - result = <build>no ; - } } result += <define>BOOST_THREAD_DONT_USE_CHRONO ; if ! [ configure.builds has_atomic_flag_lockfree 2. Once this patch is applied, the library is built but there are errors when compiling libs/thread/src/pthread/thread.cpp. The command that is run by b2 is given below. Here are the errors: libs/thread/src/pthread/thread.cpp:541:2: error: #error #error ^~~~~ In file included from ./boost/thread/thread_only.hpp:17:0, from libs/thread/src/pthread/thread.cpp:11: ./boost/thread/pthread/thread_data.hpp: In member function ‘void boost::thread_attributes::set_stack_size(std::size_t)’: ./boost/thread/pthread/thread_data.hpp:53:35: error: ‘getpagesize’ was not declared in this scope std::size_t page_size = getpagesize(); The first error is because apparently neither BOOST_HAS_SCHED_YIELD nor BOOST_HAS_PTHREAD_YIELD is defined. I understand that the 2nd error comes from the fact that getpagesize() is not in unistd.h provided by mingw-w64. There is a strange thing about the command line: it contains -mthreads although I never provided it. I tried to remove it or replace it with -pthread or -lptread but I still get the same error message. "i686-w64-mingw32-g++-7.1.0" -ftemplate-depth-128 -std=c++14 -O2 -DNDEBUG -O3 -finline-functions -Wno-inline -Wall -pedantic -march=i686 -mthreads -m32 -Wextra -Wno-long-long -Wno-unused-parameter -Wunused-function -pedantic -DBOOST_ALL_NO_LIB=1 -DBOOST_LOG_WITHOUT_EVENT_LOG -DB OOST_SYSTEM_STATIC_LINK=1 -DBOOST_THREAD_BUILD_LIB=1 -DBOOST_THREAD_DONT_USE_CHRONO -DBOOST_THREAD_POSIX -DBOOST_USE_WINDOWS_H -DNDEBUG -DWIN32_LEAN_AND_MEAN -I"." -c -o "bin.v2/libs/thread/build/gcc-mingw-7.1.0/release/boost.locale.iconv-on/boost.locale.icu-off/boost.locale.std-o ff/link-static/target-os-windows/threading-multi/pthread/thread.o" "libs/thread/src/pthread/thread.cpp"