Cmake从项目路径链接共享库

Question

我正在尝试为c++项目配置cmake并链接我的库。由于某些原因，我不能让cmake在./lib//文件夹中找到我的库。根据文档，库搜索路径应该是/lib/。

我尝试过使用空前缀和"./“，但这两种情况都没有找到我的库。

如果我在find_library()中给出提示，那么它就被找到了，但是为什么没有提示就找不到它呢？

这是我的CMakeList.txt：

cmake_minimum_required(VERSION 3.0.0)
project(UntitledProject VERSION 0.1.0)

include(CTest)
enable_testing()

message("ARCH: " ${CMAKE_LIBRARY_ARCHITECTURE})
message("PREFIX: " ${CMAKE_PREFIX_PATH})
message("LIB: " ${CMAKE_LIBRARY_PATH})

find_library(LIBMYLIB mylibrary)
message("MYLIB: " ${LIBMYLIB})

add_executable(UntitledProject main.cpp)

set(CPACK_PROJECT_NAME ${PROJECT_NAME})
set(CPACK_PROJECT_VERSION ${PROJECT_VERSION})
include(CPack)

共享库确实存在：

$ file lib/x86_64-linux-gnu/libmylibrary.so
lib/x86_64-linux-gnu/libmylibrary.so: ELF 64-bit LSB shared object, x86-64, version 1 (SYSV), dynamically linked, BuildID[sha1]=e34ba5ae24d6a09bfb847a46cd669ea7e101e8a4, stripped

这是cmake configure的输出：

[cmake] The C compiler identification is GNU 7.5.0
[cmake] The CXX compiler identification is GNU 7.5.0
[cmake] Check for working C compiler: /usr/bin/x86_64-linux-gnu-gcc-7
[cmake] Check for working C compiler: /usr/bin/x86_64-linux-gnu-gcc-7 -- works
[cmake] Detecting C compiler ABI info
[cmake] Detecting C compiler ABI info - done
[cmake] Detecting C compile features
[cmake] Detecting C compile features - done
[cmake] Check for working CXX compiler: /usr/bin/x86_64-linux-gnu-g++-7
[cmake] Check for working CXX compiler: /usr/bin/x86_64-linux-gnu-g++-7 -- works
[cmake] Detecting CXX compiler ABI info
[cmake] Detecting CXX compiler ABI info - done
[cmake] Detecting CXX compile features
[cmake] Detecting CXX compile features - done
[cmake] ARCH: x86_64-linux-gnu
[cmake] PREFIX: 
[cmake] LIB: 
[cmake] MYLIB: LIBMYLIB-NOTFOUND
[cmake] Configuring done
[cmake] Generating done

我遗漏了什么？

Answer 1

也许您可以尝试使用命令行中的绝对路径而不是./来设置CMAKE_PREFIX_PATH

Answer 2

如果我在find_library()中给出提示，那么它就被找到了，但是为什么没有提示就找不到它呢？

因为在默认情况下，find_library在系统路径中进行搜索，在Linux中，该路径通常是/usr/lib或/usr/local/lib。

要修复此问题，可以创建从lib/x86_64-linux-gnu/到/usr/local/lib的符号链接

sudo ln -s lib/x86_64-linux-gnu/libmylibrary.so /usr/local/lib/libmylibrary.so