如何配置CMake使用-fPIC构建库？

Question

我正在尝试使用-fPIC指定的创建静态库.

add_library(cpp-netlib_pic
    STATIC
    ${SRCS})
set_property(TARGET cpp-netlib_pic PROPERTY POSITION_INDEPENDENT_CODE)

这不起作用.

library(cpp-netlib_pic)是在没有-fPIC标志的情况下构建的.

然而,链接的其他目标cpp-netlib_pic 确实已-fPIC添加到其编译器标志中,但链接失败,因为cpp-netlib_pic没有.

这里foo将-fPIC添加:

add_library(foo
    SHARED
    ${SRCS})
target_link_libraries(foo cpp-netlib_pic)

我用make VERBOSE = 1证明了这一点

[ 87%] Building CXX object third_party/cpp-netlib/CMakeFiles/cpp-netlib_pic.dir/src/server_request_parsers_impl.cpp.o
/usr/bin/c++   ... -std=c++14 -Werror -Wall -Wextra ... \
    -o CMakeFiles/cpp-netlib_pic.dir/src/server_request_parsers_impl.cpp.o \
    -c .../third_party/cpp-netlib/src/server_request_parsers_impl.cpp

请注意-fPIC这里没有.

当建立foo使用的目标时cpp-netlib_pic,-fPIC出现:

[ 93%] Building CXX object foo.cc.o
/usr/bin/c++  ... -std=c++14 -Werror -Wall -Wextra ... -fPIC ... \
    -o CMakeFiles/foo_shared_lib.dir/foo.cc.o \
    -c .../foo/foo.cc

如何配置CMake以构建第一个库(cpp-netlib_pic)-fPIC？

Answer 1

你好像忘记了ON:

set_property(TARGET cpp-netlib_pic PROPERTY POSITION_INDEPENDENT_CODE ON)