Ero*_*mic 7 c++ windows gcc mingw openmp
我有一个使用OpenMP的CMake项目,可以在linux上运行.当我在我的Windows机器上编译它时,看起来CMake很难找到mingw的gcc的openmp标志.
我决定尝试一个较小的测试用例,然后编译main_openmp.c
#include <omp.h>
#include <stdio.h>
int main(int argc, char* argv[]) {
int id;
#pragma omp parallel private(id)
{
id = omp_get_thread_num();
printf("%d: Hello World!\n", id);
}
return 0;
}
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然后当我尝试编译
gcc -o OpenMPTest2 main_testomp.c -fopenmp
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我明白了
>>> gcc -o OpenMPTest2 main_testomp.c -fopenmp
c:/mingw/bin/../lib/gcc/mingw32/4.8.1/../../../../mingw32/bin/ld.exe: cannot find -lpthread
collect2.exe: error: ld returned 1 exit status
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我试图在线找到解决方案并尝试了-lgomp,-lpthreadgc2和-lpthreadvc2的变体,没有任何改进.
我以递归方式搜索了我的C:\ MinGw目录中包含lpthread的任何文件名并得到了这个:
C:\MinGW\bin\pthreadgc2.dll
C:\MinGW\bin\pthreadgce2.dll
C:\MinGW\var\cache\mingw-get\packages\pthreads-w32-2.9.1-1-mingw32-dll.tar.lzma
C:\MinGW\var\lib\mingw-get\data\mingw32-pthreads-w32.xml
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我不确定我是否错过了旗帜或包裹,或者我做错了什么.好的方法是gcc -v的输出
Using built-in specs.
COLLECT_GCC=gcc
COLLECT_LTO_WRAPPER=c:/mingw/bin/../libexec/gcc/mingw32/4.8.1/lto-wrapper.exe
Target: mingw32
Configured with: ../gcc-4.8.1/configure --prefix=/mingw --host=mingw32 --build=mingw32 --without-pic
--enable-shared --enable-static --with-gnu-ld --enable-lto --enable-libssp --disable-multilib --ena
ble-languages=c,c++,fortran,objc,obj-c++,ada --disable-sjlj-exceptions --with-dwarf2 --disable-win32
-registry --enable-libstdcxx-debug --enable-version-specific-runtime-libs --with-gmp=/usr/src/pkg/gm
p-5.1.2-1-mingw32-src/bld --with-mpc=/usr/src/pkg/mpc-1.0.1-1-mingw32-src/bld --with-mpfr= --with-sy
stem-zlib --with-gnu-as --enable-decimal-float=yes --enable-libgomp --enable-threads --with-libiconv
-prefix=/mingw32 --with-libintl-prefix=/mingw --disable-bootstrap LDFLAGS=-s CFLAGS=-D_USE_32BIT_TIM
E_T
Thread model: win32
gcc version 4.8.1 (GCC)
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知道什么是错的吗?
Ero*_*mic 20
我终于能够把事情搞定了.
首先,使用mingw-get我安装了mingw32-pthreads-w32
这允许我在gcc中使用-fopenmp标志.
但是当使用CMake时我必须包括以下行:
message(STATUS "Checking OpenMP")
find_package(OpenMP)
IF(OPENMP_FOUND)
message("Found OpenMP! ^_^")
# add flags for OpenMP
set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${OpenMP_C_FLAGS}")
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${OpenMP_CXX_FLAGS}")
set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} ${OpenMP_SHARED_LINKER_FLAGS}")
set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} ${OpenMP_EXE_LINKER_FLAGS}")
ELSE()
message("Missed OpenMP! x_x")
ENDIF()
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像往常一样,但我还必须确保在target_link_libraries命令中有OpenMP_CXX_FLAGS
set(SOURCE_FILES
src/foo.cpp
src/bar.cpp
src/baz.cpp)
add_library(<mylib> SHARED ${SOURCE_FILES})
target_link_libraries(<mylib> ${OpenMP_CXX_FLAGS})
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