我正在尝试使用 Cmake
将外部库安装到我的 C++ 项目中。我希望使用该库生成 Xcode
项目。在我的终端中,我从构建目录运行以下命令:
cmake -G Xcode ..
这给了我以下错误:
-- The CXX compiler identification is unknown
-- The C compiler identification is unknown
CMake Error at CMakeLists.txt:6 (project):
No CMAKE_CXX_COMPILER could be found.
CMake Error at CMakeLists.txt:6 (project):
No CMAKE_C_COMPILER could be found.
我正在使用 g++ 编译器:
Configured with: --prefix=/Library/Developer/CommandLineTools/usr --with-gxx-include-dir=/usr/include/c++/4.2.1
Apple LLVM version 7.0.0 (clang-700.1.76)
Target: x86_64-apple-darwin14.5.0
Thread model: posix
编辑:CMakeLists.txt 文件
file(READ "${CMAKE_CURRENT_SOURCE_DIR}/VERSION" PROJECT_VERSION_FULL)
string(REGEX REPLACE "[\n\r]" "" PROJECT_VERSION_FULL "${PROJECT_VERSION_FULL}")
string(REGEX REPLACE "^([0-9]+)\\.[0-9]+\\.[0-9]+$" "\\1" PROJECT_VERSION_MAJOR "${PROJECT_VERSION_FULL}")
string(REGEX REPLACE "^[0-9]+\\.([0-9]+)\\.[0-9]+$" "\\1" PROJECT_VERSION_MINOR "${PROJECT_VERSION_FULL}")
string(REGEX REPLACE "^[0-9]+\\.[0-9]+\\.([0-9]+)$" "\\1" PROJECT_VERSION_PATCH "${PROJECT_VERSION_FULL}")
set(PROJECT_VERSION "${PROJECT_VERSION_MAJOR}.${PROJECT_VERSION_MINOR}")
math(EXPR LIBRARY_VERSION_MAJOR "${PROJECT_VERSION_MAJOR}")
set(LIBRARY_VERSION_MINOR "${PROJECT_VERSION_MINOR}")
set(LIBRARY_VERSION_PATCH "${PROJECT_VERSION_PATCH}")
set(LIBRARY_VERSION "${LIBRARY_VERSION_MAJOR}.${LIBRARY_VERSION_MINOR}")
set(LIBRARY_VERSION_FULL "${LIBRARY_VERSION}.${LIBRARY_VERSION_PATCH}")
option(CODE_COVERAGE "Set ON to add code coverage compile options" OFF)
option(GENERATE_DOC "Set ON to genrate doxygen API reference in build/doc directory" OFF)
# C++11 compiler Check
if(NOT CMAKE_CXX_COMPILER_VERSION) # work around for cmake versions smaller than 2.8.10
execute_process(COMMAND ${CMAKE_CXX_COMPILER} -dumpversion OUTPUT_VARIABLE CMAKE_CXX_COMPILER_VERSION)
endif()
if(CMAKE_CXX_COMPILER MATCHES ".*clang" OR CMAKE_CXX_COMPILER_ID STREQUAL "Clang")
set(CMAKE_COMPILER_IS_CLANGXX 1)
endif()
if( (CMAKE_COMPILER_IS_GNUCXX AND ${CMAKE_CXX_COMPILER_VERSION} VERSION_LESS 4.7) OR
(CMAKE_COMPILER_IS_CLANGXX AND ${CMAKE_CXX_COMPILER_VERSION} VERSION_LESS 3.2))
message(FATAL_ERROR "Your C++ compiler does not support C++11. Please install g++ 4.7 (or greater) or clang 3.2 (or greater)")
else()
message(STATUS "Compiler is recent enough to support C++11.")
endif()
if( CMAKE_COMPILER_IS_GNUCXX )
append_cxx_compiler_flags("-std=c++11 -Wall -Wextra -DNDEBUG" "GCC" CMAKE_CXX_FLAGS)
append_cxx_compiler_flags("-O3 -ffast-math -funroll-loops" "GCC" CMAKE_CXX_OPT_FLAGS)
if ( CODE_COVERAGE )
append_cxx_compiler_flags("-g -fprofile-arcs -ftest-coverage -lgcov" "GCC" CMAKE_CXX_FLAGS)
endif()
else()
if(MSVC)
append_cxx_compiler_flags("/EHsc" "MSVC" CMAKE_CXX_FLAGS)
append_cxx_compiler_flags("/Od" "MSVC" CMAKE_CXX_FLAGS_DEBUG)
append_cxx_compiler_flags("/Ox" "MSVC" CMAKE_CXX_FLAGS_RELEASE)
set(vars CMAKE_CXX_FLAGS CMAKE_CXX_FLAGS_DEBUG CMAKE_CXX_FLAGS_RELEASE CMAKE_CXX_FLAGS_MINSIZEREL CMAKE_CXX_FLAGS_RELWITHDEBINFO)
foreach(var ${vars})
string(REPLACE "/MD" "-MT" ${var} "${${var}}")
endforeach(var)
add_definitions("/DMSVC_COMPILER")
else()
append_cxx_compiler_flags("-std=c++11 -DNDEBUG" "CLANG" CMAKE_CXX_FLAGS)
append_cxx_compiler_flags("-stdlib=libc++" "CLANG" CMAKE_CXX_FLAGS)
append_cxx_compiler_flags("-O3 -ffast-math -funroll-loops" "CLANG" CMAKE_CXX_OPT_FLAGS)
endif()
endif()
还有 CMakeEdit.log:
Compiling the CXX compiler identification source file "CMakeCXXCompilerId.cpp" failed.
Compiler:
Build flags:
Id flags:
The output was:
1
xcode-select: error: tool 'xcodebuild' requires Xcode, but active developer directory '/Library/Developer/CommandLineTools' is a command line tools instance
Compiling the C compiler identification source file "CMakeCCompilerId.c" failed.
Compiler:
Build flags:
Id flags:
The output was:
1
xcode-select: error: tool 'xcodebuild' requires Xcode, but active developer directory '/Library/Developer/CommandLineTools' is a command line tools instance
编辑:
当 xcode-select 开发者目录指向/Library/Developer/CommandLineTools 时,当需要完整的常规 XCode(在 XCode 之后安装 CLT 时发生)时,会发生此问题。
我发现解决办法是这样的:
sudo xcode-select -s /Applications/Xcode.app/Contents/Developer
完成此操作后,当我运行 cmake -G Xcode ..
时出现其他错误:
-- The CXX compiler identification is AppleClang 7.0.0.7000176
-- The C compiler identification is AppleClang 7.0.0.7000176
CMake Error at /usr/local/Cellar/cmake/3.4.0/share/cmake/Modules/Platform/Darwin.cmake:76 (message):
CMAKE_OSX_DEPLOYMENT_TARGET is '10.10' but CMAKE_OSX_SYSROOT:
""
is not set to a MacOSX SDK with a recognized version. Either set
CMAKE_OSX_SYSROOT to a valid SDK or set CMAKE_OSX_DEPLOYMENT_TARGET to
empty.
Call Stack (most recent call first):
/usr/local/Cellar/cmake/3.4.0/share/cmake/Modules/CMakeSystemSpecificInformation.cmake:36 (include)
CMakeLists.txt:6 (project)
编辑 2 好像是操作系统指定的SDK不对。
CMAKE_OSX_DEPLOYMENT_TARGET is '10.10' but the matching SDK does not exist
at:
"/Applications/DEV/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.10.sdk"
Instead using SDK:
"/Applications/DEV/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.11.sdk".
Call Stack (most recent call first):
/usr/local/Cellar/cmake/3.4.0/share/cmake/Modules/CMakeSystemSpecificInitialize.cmake:18 (include)
CMakeLists.txt:6 (project)
-- The CXX compiler identification is AppleClang 7.0.0.7000176
-- The C compiler identification is AppleClang 7.0.0.7000176
CMake Error at /usr/local/Cellar/cmake/3.4.0/share/cmake/Modules/Platform/Darwin.cmake:76 (message):
CMAKE_OSX_DEPLOYMENT_TARGET is '10.10' but CMAKE_OSX_SYSROOT:
""
is not set to a MacOSX SDK with a recognized version. Either set
CMAKE_OSX_SYSROOT to a valid SDK or set CMAKE_OSX_DEPLOYMENT_TARGET to
empty.
Call Stack (most recent call first):
/usr/local/Cellar/cmake/3.4.0/share/cmake/Modules/CMakeSystemSpecificInformation.cmake:36 (include)
CMakeLists.txt:6 (project)
最佳答案
我遇到了同样的问题,但我解决了:
sudo xcode-select --reset
在执行上述操作之前,xcode-select -p
报告路径为 /Library/Developer/CommandLineTools
。
重置后路径为/Applications/Xcode.app/Contents/Developer
。
关于c++ - CXX 编译器标识未知 : xcode,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/33998853/