我正在为跨平台构建Boost Asio的timer example。所以我使用CMake自动化构建系统。
文件结构：
- timer
- build (Just empty)
- dep
- boost
- boost
- doc
- libs
- ...
- CMakeLists.txt (Important)
- ...
- CMakeLists.txt
- src
- CMakeLists.txt
- timer.cpp
- CMakeLists.txt
除dep/boost/CMakeLists.txt之外的其他CMake脚本只是在子目录中包含一些脚本或配置项目，就是这样！
DEP /升压/的CMakeLists.txt：
# Boost settings
set(BOOST_ROOT ${CMAKE_CURRENT_LIST_DIR})
set(Boost_USE_STATIC_LIBS ON)
set(Boost_USE_MULTITHREADED ON)
set(Boost_USE_STATIC_RUNTIME ON)
# Specify Boost libraries that will use.
set(boost_components system date_time regex)
set(boost_components_option --with-system --with-date_time --with-regex)
# Find compiled Boost
find_package(Boost COMPONENTS ${boost_components}) <-- STMT1
# If couldn't find it, compile Boost before process.
if(NOT ${Boost_FOUND})
if(WIN32)
set(bootstrap_name bootstrap.bat)
set(bootstrap_command bootstrap.bat)
set(b2_name b2.exe)
set(b2_command b2.exe)
set(b2_variant debug,release)
else()
set(bootstrap_name bootstrap.sh)
set(bootstrap_command ./bootstrap.sh)
set(b2_name b2)
set(b2_command ./b2)
set(b2_variant release)
endif()
if(EXISTS ${CMAKE_CURRENT_LIST_DIR}/${bootstrap_name})
if(NOT EXISTS ${CMAKE_CURRENT_LIST_DIR}/${b2_name})
if(UNIX)
execute_process(COMMAND chmod +x
${bootstrap_name} tools/build/src/engine/build.sh
WORKING_DIRECTORY ${CMAKE_CURRENT_LIST_DIR})
endif()
execute_process(COMMAND ${bootstrap_command}
WORKING_DIRECTORY ${CMAKE_CURRENT_LIST_DIR})
endif()
else()
message(FATAL_ERROR "Could NOT find ${bootstrap_name}")
endif()
if(EXISTS ${CMAKE_CURRENT_LIST_DIR}/${b2_name})
execute_process(COMMAND ${b2_command} ${boost_components_option}
variant=${b2_variant} link=static threading=multi
runtime-link=static
WORKING_DIRECTORY ${CMAKE_CURRENT_LIST_DIR})
else()
message(FATAL_ERROR "Could NOT find ${b2_name}")
endif()
# After compile Boost, re-find it.
find_package(Boost REQUIRED COMPONENTS ${boost_components}) <-- STMT2
endif()
好的......当我在控制台上的cmake ..目录中命令build时，它在Windows 10上运行得很好，但在Ubuntu 14.04上出现问题。问题是CMake无法在编译之后找到Boost库（Boost库，在STMT2）。那不是全部。奇怪的是，如果在cmake ..目录中只有build命令（在STMT1中完全相同），CMake会毫无问题地找到它。可以理解的是，在发生问题之前，所有必需的Boost库都在dep/boost/stage/lib目录中编译。显然，STMT1和STMT2完全相同，只是指定了REQUIRED。我检查了一些与Boost相关的变量，并用适当的值重新声明它，但它无法帮助我。
第一个命令控制台输出：
user@user-pc:~/desktop/timer/build$ cmake ..
-- The C compiler identification is GNU 4.8.2
-- The CXX compiler identification is GNU 4.8.2
-- 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
-- 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
-- Could NOT find Boost
Building Boost.Build engine with toolset gcc... tools/build/src/engine/bin.linuxx86_64/b2
Detecting Python version... 2.7
Detecting Python root... /usr
Unicode/ICU support for Boost.Regex?... not found.
Generating Boost.Build configuration in project-config.jam...
Bootstrapping is done. To build, run:
./b2
To adjust configuration, edit 'project-config.jam'.
Further information:
- Command line help:
./b2 --help
- Getting started guide:
http://www.boost.org/more/getting_started/unix-variants.html
- Boost.Build documentation:
http://www.boost.org/build/doc/html/index.html
Performing configuration checks
- 32-bit : no
- 64-bit : yes
- arm : no
- mips1 : no
- power : no
- sparc : no
- x86 : yes
Building the Boost C++ Libraries.
- has_icu builds : no
Component configuration:
- atomic : not building
- chrono : not building
- container : not building
- context : not building
- coroutine : not building
- date_time : building
- exception : not building
- filesystem : not building
- graph : not building
- graph_parallel : not building
- iostreams : not building
- locale : not building
- log : not building
- math : not building
- mpi : not building
- program_options : not building
- python : not building
- random : not building
- regex : building
- serialization : not building
- signals : not building
- system : building
- test : not building
- thread : not building
- timer : not building
- wave : not building
...patience...
...found 1092 targets...
...updating 51 targets...
common.mkdir stage
common.mkdir stage/lib
common.mkdir bin.v2/libs/date_time
common.mkdir bin.v2/libs/date_time/build
common.mkdir bin.v2/libs/date_time/build/gcc-4.8
common.mkdir bin.v2/libs/date_time/build/gcc-4.8/release
common.mkdir bin.v2/libs/date_time/build/gcc-4.8/release/link-static
common.mkdir bin.v2/libs/date_time/build/gcc-4.8/release/link-static/runtime-link-static
common.mkdir bin.v2/libs/date_time/build/gcc-4.8/release/link-static/runtime-link-static/threading-multi
common.mkdir bin.v2/libs/date_time/build/gcc-4.8/release/link-static/runtime-link-static/threading-multi/gregorian
gcc.compile.c++ bin.v2/libs/date_time/build/gcc-4.8/release/link-static/runtime-link-static/threading-multi/gregorian/greg_month.o
gcc.compile.c++ bin.v2/libs/date_time/build/gcc-4.8/release/link-static/runtime-link-static/threading-multi/gregorian/greg_weekday.o
gcc.compile.c++ bin.v2/libs/date_time/build/gcc-4.8/release/link-static/runtime-link-static/threading-multi/gregorian/date_generators.o
gcc.archive bin.v2/libs/date_time/build/gcc-4.8/release/link-static/runtime-link-static/threading-multi/libboost_date_time.a
common.copy stage/lib/libboost_date_time.a
common.mkdir bin.v2/libs/regex/build/gcc-4.8/release
common.mkdir bin.v2/libs/regex/build/gcc-4.8/release/link-static
common.mkdir bin.v2/libs/regex/build/gcc-4.8/release/link-static/runtime-link-static
common.mkdir bin.v2/libs/regex/build/gcc-4.8/release/link-static/runtime-link-static/threading-multi
gcc.compile.c++ bin.v2/libs/regex/build/gcc-4.8/release/link-static/runtime-link-static/threading-multi/c_regex_traits.o
gcc.compile.c++ bin.v2/libs/regex/build/gcc-4.8/release/link-static/runtime-link-static/threading-multi/cpp_regex_traits.o
gcc.compile.c++ bin.v2/libs/regex/build/gcc-4.8/release/link-static/runtime-link-static/threading-multi/cregex.o
gcc.compile.c++ bin.v2/libs/regex/build/gcc-4.8/release/link-static/runtime-link-static/threading-multi/fileiter.o
gcc.compile.c++ bin.v2/libs/regex/build/gcc-4.8/release/link-static/runtime-link-static/threading-multi/icu.o
gcc.compile.c++ bin.v2/libs/regex/build/gcc-4.8/release/link-static/runtime-link-static/threading-multi/instances.o
gcc.compile.c++ bin.v2/libs/regex/build/gcc-4.8/release/link-static/runtime-link-static/threading-multi/posix_api.o
gcc.compile.c++ bin.v2/libs/regex/build/gcc-4.8/release/link-static/runtime-link-static/threading-multi/regex.o
gcc.compile.c++ bin.v2/libs/regex/build/gcc-4.8/release/link-static/runtime-link-static/threading-multi/regex_debug.o
gcc.compile.c++ bin.v2/libs/regex/build/gcc-4.8/release/link-static/runtime-link-static/threading-multi/regex_raw_buffer.o
gcc.compile.c++ bin.v2/libs/regex/build/gcc-4.8/release/link-static/runtime-link-static/threading-multi/regex_traits_defaults.o
gcc.compile.c++ bin.v2/libs/regex/build/gcc-4.8/release/link-static/runtime-link-static/threading-multi/static_mutex.o
gcc.compile.c++ bin.v2/libs/regex/build/gcc-4.8/release/link-static/runtime-link-static/threading-multi/w32_regex_traits.o
gcc.compile.c++ bin.v2/libs/regex/build/gcc-4.8/release/link-static/runtime-link-static/threading-multi/wc_regex_traits.o
gcc.compile.c++ bin.v2/libs/regex/build/gcc-4.8/release/link-static/runtime-link-static/threading-multi/wide_posix_api.o
gcc.compile.c++ bin.v2/libs/regex/build/gcc-4.8/release/link-static/runtime-link-static/threading-multi/winstances.o
gcc.compile.c++ bin.v2/libs/regex/build/gcc-4.8/release/link-static/runtime-link-static/threading-multi/usinstances.o
gcc.archive bin.v2/libs/regex/build/gcc-4.8/release/link-static/runtime-link-static/threading-multi/libboost_regex.a
common.copy stage/lib/libboost_regex.a
common.mkdir bin.v2/libs/system
common.mkdir bin.v2/libs/system/build
common.mkdir bin.v2/libs/system/build/gcc-4.8
common.mkdir bin.v2/libs/system/build/gcc-4.8/release
common.mkdir bin.v2/libs/system/build/gcc-4.8/release/link-static
common.mkdir bin.v2/libs/system/build/gcc-4.8/release/link-static/runtime-link-static
common.mkdir bin.v2/libs/system/build/gcc-4.8/release/link-static/runtime-link-static/threading-multi
gcc.compile.c++ bin.v2/libs/system/build/gcc-4.8/release/link-static/runtime-link-static/threading-multi/error_code.o
gcc.archive bin.v2/libs/system/build/gcc-4.8/release/link-static/runtime-link-static/threading-multi/libboost_system.a
common.copy stage/lib/libboost_system.a
...updated 51 targets...
The Boost C++ Libraries were successfully built!
The following directory should be added to compiler include paths:
/home/user/desktop/timer/dep/boost
The following directory should be added to linker library paths:
/home/user/desktop/timer/dep/boost/stage/lib
CMake Error at /usr/share/cmake-2.8/Modules/FindBoost.cmake:1131 (message):
Unable to find the requested Boost libraries.
Boost version: 1.58.0
Boost include path: /home/user/desktop/timer/dep/boost
Could not find the following static Boost libraries:
boost_system
boost_date_time
boost_regex
No Boost libraries were found. You may need to set BOOST_LIBRARYDIR to the
directory containing Boost libraries or BOOST_ROOT to the location of
Boost.
Call Stack (most recent call first):
dep/boost/CMakeLists.txt:50 (find_package)
dep/CMakeLists.txt:2 (include)
CMakeLists.txt:6 (include)
-- Configuring incomplete, errors occurred!
See also "/home/user/desktop/timer/build/CMakeFiles/CMakeOutput.log".
第二个命令控制台输出：
user@user-pc:~/desktop/timer/build$ cmake ..
-- Boost version: 1.58.0
-- Found the following Boost libraries:
-- system
-- date_time
-- regex
-- Configuring done
-- Generating done
-- Build files have been written to: /home/user/desktop/timer/build
到底发生了什么？以及如何解决？感谢。