Question

要重现我的问题...我download Boost，然后我运行booststrap和b2 --build-dir=C:\Users\xxx\Downloads\my_boost_build_dir --prefix=C:\Users\xxx\Downloads\my_boost_install_dir --layout=system variant=release link=static install。一切看起来都那么好。提供的前缀（安装）目录中填充了headers和libs。

但是这里的事情开始出错了。如果我写下面的cmake文件...

find_package(Boost REQUIRED)

message("Boost_FOUND" ${Boost_FOUND})
message("Boost_INCLUDE_DIRS" ${Boost_INCLUDE_DIRS})
message("Boost_LIBRARY_DIRS" ${Boost_LIBRARY_DIRS})
message("Boost_LIBRARIES" ${Boost_LIBRARIES})
message("Boost_CHRONO_FOUND" ${Boost_CHRONO_FOUND})
message("Boost_CHRONO_LIBRARY" ${Boost_CHRONO_LIBRARY})

add_executable(main main.cpp)
target_link_libraries(main PRIVATE Boost::boost Boost::chrono)

...我用boost install dir cmake .. -DCMAKE_PREFIX_PATH=C:\Users\xxx\Downloads\my_boost_install_dir的路径配置它，然后我得到以下输出和错误......

Boost_FOUND1
Boost_INCLUDE_DIRSC:/Users/xxx/Downloads/my_boost_install_dir/include
Boost_LIBRARY_DIRSC:/Users/xxx/Downloads/my_boost_install_dir/lib
Boost_LIBRARIES
Boost_CHRONO_FOUND
Boost_CHRONO_LIBRARY
-- Configuring done
CMake Error at CMakeLists.txt:14 (add_executable):
  Target "main" links to target "Boost::chrono" but the target was not found.
  Perhaps a find_package() call is missing for an IMPORTED target, or an
  ALIAS target is missing?

发现了Boost，找到了include和lib dirs，但是chrono库（以及所有其他库）却没有。也许我需要明确命名我的组件？所以我尝试了这个cmake ......

find_package(Boost REQUIRED COMPONENTS chrono)

message("Boost_FOUND" ${Boost_FOUND})
message("Boost_INCLUDE_DIRS" ${Boost_INCLUDE_DIRS})
message("Boost_LIBRARY_DIRS" ${Boost_LIBRARY_DIRS})
message("Boost_LIBRARIES" ${Boost_LIBRARIES})
message("Boost_CHRONO_FOUND" ${Boost_CHRONO_FOUND})
message("Boost_CHRONO_LIBRARY" ${Boost_CHRONO_LIBRARY})

add_executable(main main.cpp)
target_link_libraries(main PRIVATE Boost::boost Boost::chrono)

但这会产生以下输出和错误。

CMake Error at C:/Program Files/CMake/share/cmake-3.9/Modules/FindBoost.cmake:1877 (message):
  Unable to find the requested Boost libraries.

  Boost version: 1.64.0

  Boost include path: C:/Users/xxx/Downloads/my_boost_install_dir/include

  Could not find the following Boost libraries:

          boost_chrono

  Some (but not all) of the required Boost libraries were found.  You may
  need to install these additional Boost libraries.  Alternatively, set
  BOOST_LIBRARYDIR to the directory containing Boost libraries or BOOST_ROOT
  to the location of Boost.
Call Stack (most recent call first):
  CMakeLists.txt:5 (find_package)

Boost_FOUND0
Boost_INCLUDE_DIRSC:/Users/xxx/Downloads/my_boost_install_dir/include
Boost_LIBRARY_DIRS
Boost_LIBRARIES
Boost_CHRONO_FOUND
Boost_CHRONO_LIBRARY

和以前一样，它发现了boost和标题，但由于某些原因它无法找到库。

Answer 1

If you want to use specific (non-header-only) Boost components, you have to specify them in find_package. In your case:

find_package(Boost COMPONENTS chrono REQUIRED)

Answer 2

根据https://cmake.org/cmake/help/v3.0/module/FindBoost.html

find_package（Boost）按照下面的提示查找boost目录：

BOOST_ROOT - 首选安装前缀（或BOOSTROOT）

BOOST_INCLUDEDIR - 首选包含目录，例如   /包括

BOOST_LIBRARYDIR - 首选的库目录，例如/ lib中

Boost_NO_SYSTEM_PATHS - 设置为ON以禁用在位置搜索   不                            由这些提示变量指定。默认为OFF。

Boost_ADDITIONAL_VERSIONS                           - 此模块未知的Boost版本列表                            （Boost安装位置可能包含版本）

如果您不知道放置boost库和包含文件的默认位置在哪里，则应在find_package之前设置这些变量。

MSVC构建Boost但Cmake findBoost不起作用？

2 个答案: