我有一个CMake项目,同时构建一个静态库,并将其与其他代码链接到一个可执行文件中。由于我不会进入的原因,我希望使用--whole-archive
链接器标志进行此链接。
现在,这个标志很棘手,因为你不能把它添加到任何地方 - 你必须切换它,然后列出你想要它应用的库,然后取消它。
我已经读过某个地方(URL逃避了我),如果你有一个预先存在的库,你可以通过执行以下操作有效地添加这个链接器标志:
# Just an example, find_library calls should really be isolated to separate find modules
find_library(FOO_LIBRARY foo)
set(FOO_LIBRARY "-Wl,--whole-archive ${FOO_LIBRARY} -Wl,--no-whole-archive")
add_executable(hello main.c)
target_link_libraries(hello ${FOO_LIBRARY})
那没关系。但是,如果它是一个静态库,你正在建立一个你没有预先存在的变量(即你有一个add_library()
CMake命令的东西)?您是否必须手动指示其路径而不是$ {FOO_LIBRARY}?或者是否有其他一些技巧可以用来获取CMake为它命令行的路径?
此外,如果我使用某种类似${FOO_LIBRARY}
的字符串而不是我的静态库目标标识符 - 我相信CMake可能会错过依赖项,即它可能不会与修改后的库重新链接(或者甚至不构建它),因为target_link_libraries命令将看到一个奇怪的字符串而不是另一个目标的标识符。
这可以使用:
add_dependencies(the_exe the_static_lib)
set_target_properties(the_exe LINK_FLAGS
"-L/path/to/the_static_lib -Wl,--whole-archive,-lthe_static_lib,--no-whole-archive")
-L/path/to/the_static_lib
的值从您指定目标的输出目录的内容透明地进行,如果不指定,则遵循目标的默认输出目录。例如。如果the_static_lib
只是在构建目录中输出,那么-L/path/to/the_static_lib
将是-L.
这是一个以相当一般的方式进行说明的项目,其中我们构建了源和头的子目录以及不同的传统输出目录,bin
,lib
$ ls -R
.:
app build CMakeLists.txt foobar inc
./app:
main.c
./build:
./foobar:
bar.c foo.c
./inc:
foobar.h
有文件:
应用程序/ main.c中
#include <foobar.h>
int main(void)
{
foo();
bar();
return 0;
}
foobar的/ foo.c的
#include <foobar.h>
#include <stdio.h>
void foo(void)
{
puts(__func__);
}
foobar的/ bar.c
#include <foobar.h>
#include <stdio.h>
void bar(void)
{
puts(__func__);
}
INC / foobar.h中
#ifndef FOOBAR_H
#define FOOBAR_H
void foo(void);
void bar(void);
#endif
CMakeLists.txt(1)
cmake_minimum_required(VERSION 3.0)
project(app)
include_directories(inc)
add_library(foobar STATIC foobar/foo.c foobar/bar.c)
set_target_properties(foobar
PROPERTIES ARCHIVE_OUTPUT_DIRECTORY "${CMAKE_BINARY_DIR}/lib")
add_executable(app app/main.c)
add_dependencies(app foobar)
set_target_properties(app PROPERTIES
RUNTIME_OUTPUT_DIRECTORY "${CMAKE_BINARY_DIR}/bin"
LINK_FLAGS "-Llib -Wl,--whole-archive,-lfoobar,--no-whole-archive")
我们想从./build/lib/libfoobar.a
和./foobar/foo.c
制作./foobar/bar.c
。我们想从./build/bin/app
制作./app/main.c
,链接整个档案./build/lib/libfoobar.a
生成,构建和运行:
$ cd build; cmake ..; make; ./bin/app
-- The C compiler identification is GNU 8.2.0
-- The CXX compiler identification is GNU 8.2.0
-- Check for working C compiler: /usr/bin/cc
-- Check for working C compiler: /usr/bin/cc -- works
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Detecting C compile features
-- Detecting C compile features - done
-- Check for working CXX compiler: /usr/bin/c++
-- Check for working CXX compiler: /usr/bin/c++ -- works
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Detecting CXX compile features
-- Detecting CXX compile features - done
-- Configuring done
-- Generating done
-- Build files have been written to: /home/imk/develop/so/cmake_prob/build
Scanning dependencies of target foobar
[ 20%] Building C object CMakeFiles/foobar.dir/foobar/foo.c.o
[ 40%] Building C object CMakeFiles/foobar.dir/foobar/bar.c.o
[ 60%] Linking C static library lib/libfoobar.a
[ 60%] Built target foobar
Scanning dependencies of target app
[ 80%] Building C object CMakeFiles/app.dir/app/main.c.o
[100%] Linking C executable bin/app
[100%] Built target app
foo
bar
类似地,例如,而不是我们有CMakeLists.txt
:
CMakeLists.txt(2)
cmake_minimum_required(VERSION 3.0)
project(app)
include_directories(inc)
add_subdirectory(foobar)
add_executable(app app/main.c)
add_dependencies(app foobar)
set_target_properties(app PROPERTIES
RUNTIME_OUTPUT_DIRECTORY "${CMAKE_BINARY_DIR}/bin"
LINK_FLAGS "-Llib -Wl,--whole-archive,-lfoobar,--no-whole-archive")
并单独:
foobar / CMakeLists.txt(1)
add_library(foobar STATIC foo.c bar.c)
set_target_properties(foobar
PROPERTIES ARCHIVE_OUTPUT_DIRECTORY "${CMAKE_BINARY_DIR}/lib")
使用相同的分隔,但默认输出目录,我们有:
CMakeLists.txt(3)
cmake_minimum_required(VERSION 3.0)
project(app)
include_directories(inc)
add_subdirectory(foobar)
add_executable(app app/main.c)
add_dependencies(app foobar)
set_target_properties(app PROPERTIES
LINK_FLAGS "-Lfoobar -Wl,--whole-archive,-lfoobar,--no-whole-archive")
foobar / CMakeLists.txt(2)
add_library(foobar STATIC foo.c bar.c)
会是这样的:
$ cd build; cmake ..; make; ./app
-- The C compiler identification is GNU 8.2.0
-- The CXX compiler identification is GNU 8.2.0
-- Check for working C compiler: /usr/bin/cc
-- Check for working C compiler: /usr/bin/cc -- works
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Detecting C compile features
-- Detecting C compile features - done
-- Check for working CXX compiler: /usr/bin/c++
-- Check for working CXX compiler: /usr/bin/c++ -- works
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Detecting CXX compile features
-- Detecting CXX compile features - done
-- Configuring done
-- Generating done
-- Build files have been written to: /home/imk/develop/so/cmake_prob/build
Scanning dependencies of target foobar
[ 20%] Building C object foobar/CMakeFiles/foobar.dir/foo.c.o
[ 40%] Building C object foobar/CMakeFiles/foobar.dir/bar.c.o
[ 60%] Linking C static library libfoobar.a
[ 60%] Built target foobar
Scanning dependencies of target app
[ 80%] Building C object CMakeFiles/app.dir/app/main.c.o
[100%] Linking C executable app
[100%] Built target app
foo
bar