【发布时间】：2019-02-27 20:05:19
【问题描述】：
我正在尝试使用 CMake 在 Khadas Vim2 上构建 OpenCv，它具有基于 arm 64 位 的 cpu 架构的预安装 Ubuntu Mate。但是 CMake 无法识别 Java (where i already have both oracle-jdk-1.8 and openjdk-1.8)。我尝试重新安装 Apache Ant，将 JAVA_HOME 和 ANT_HOME 导出到 PATH 通过：
export JAVA_HOME=/usr/lib/jvm/java-8-openjdk-arm64
export PATH=$JAVA_HOME/bin:$PATH
export ANT_HOME=/usr/local/ant
export PATH=$ANT_HOME/bin:$PATH
我还尝试将工具链文件中的 GCC 和 G++ 编译器设置为：
set( CMAKE_SYSTEM_PROCESSOR arm )
set( CMAKE_C_COMPILER arm-linux-gnueabi-gcc )
set( CMAKE_CXX_COMPILER arm-linux-gnueabi-g++ )
if(COMMAND toolchain_save_config)
return() # prevent recursive call
endif()
set(CMAKE_SYSTEM_NAME Linux)
set(CMAKE_SYSTEM_VERSION 1)
if(NOT DEFINED CMAKE_SYSTEM_PROCESSOR)
set(CMAKE_SYSTEM_PROCESSOR arm)
else()
#message("CMAKE_SYSTEM_PROCESSOR=${CMAKE_SYSTEM_PROCESSOR}")
endif()
include("${CMAKE_CURRENT_LIST_DIR}/gnu.toolchain.cmake")
if(CMAKE_SYSTEM_PROCESSOR STREQUAL arm AND NOT ARM_IGNORE_FP)
set(FLOAT_ABI_SUFFIX "")
if(NOT SOFTFP)
set(FLOAT_ABI_SUFFIX "hf")
endif()
endif()
if(NOT "x${GCC_COMPILER_VERSION}" STREQUAL "x")
set(__GCC_VER_SUFFIX "-${GCC_COMPILER_VERSION}")
endif()
if(NOT DEFINED CMAKE_C_COMPILER)
find_program(CMAKE_C_COMPILER NAMES ${GNU_MACHINE}${FLOAT_ABI_SUFFIX}-gcc${__GCC_VER_SUFFIX})
else()
#message(WARNING "CMAKE_C_COMPILER=${CMAKE_C_COMPILER} is defined")
endif()
if(NOT DEFINED CMAKE_CXX_COMPILER)
find_program(CMAKE_CXX_COMPILER NAMES ${GNU_MACHINE}${FLOAT_ABI_SUFFIX}-g++${__GCC_VER_SUFFIX})
else()
#message(WARNING "CMAKE_CXX_COMPILER=${CMAKE_CXX_COMPILER} is defined")
endif()
if(NOT DEFINED CMAKE_LINKER)
find_program(CMAKE_LINKER NAMES ${GNU_MACHINE}${FLOAT_ABI_SUFFIX}-ld${__GCC_VER_SUFFIX} ${GNU_MACHINE}${FLOAT_ABI_SUFFIX}-ld)
else()
#message(WARNING "CMAKE_LINKER=${CMAKE_LINKER} is defined")
endif()
if(NOT DEFINED CMAKE_AR)
find_program(CMAKE_AR NAMES ${GNU_MACHINE}${FLOAT_ABI_SUFFIX}-ar${__GCC_VER_SUFFIX} ${GNU_MACHINE}${FLOAT_ABI_SUFFIX}-ar)
else()
#message(WARNING "CMAKE_AR=${CMAKE_AR} is defined")
endif()
if(NOT DEFINED ARM_LINUX_SYSROOT AND DEFINED GNU_MACHINE)
set(ARM_LINUX_SYSROOT /usr/${GNU_MACHINE}${FLOAT_ABI_SUFFIX})
endif()
if(NOT DEFINED CMAKE_CXX_FLAGS)
set(CMAKE_CXX_FLAGS "" CACHE INTERNAL "")
set(CMAKE_C_FLAGS "" CACHE INTERNAL "")
set(CMAKE_SHARED_LINKER_FLAGS "" CACHE INTERNAL "")
set(CMAKE_MODULE_LINKER_FLAGS "" CACHE INTERNAL "")
set(CMAKE_EXE_LINKER_FLAGS "" CACHE INTERNAL "")
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fdata-sections -Wa,--noexecstack -fsigned-char -Wno-psabi")
set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -fdata-sections -Wa,--noexecstack -fsigned-char -Wno-psabi")
if(CMAKE_SYSTEM_PROCESSOR STREQUAL arm)
set(CMAKE_CXX_FLAGS "-mthumb ${CMAKE_CXX_FLAGS}")
set(CMAKE_C_FLAGS "-mthumb ${CMAKE_C_FLAGS}")
set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -Wl,-z,nocopyreloc")
endif()
if(CMAKE_SYSTEM_PROCESSOR STREQUAL arm)
set(ARM_LINKER_FLAGS "-Wl,--fix-cortex-a8 -Wl,--no-undefined -Wl,--gc-sections -Wl,-z,noexecstack -Wl,-z,relro -Wl,-z,now")
elseif(CMAKE_SYSTEM_PROCESSOR STREQUAL aarch64)
set(ARM_LINKER_FLAGS "-Wl,--no-undefined -Wl,--gc-sections -Wl,-z,noexecstack -Wl,-z,relro -Wl,-z,now")
endif()
set(CMAKE_SHARED_LINKER_FLAGS "${ARM_LINKER_FLAGS} ${CMAKE_SHARED_LINKER_FLAGS}")
set(CMAKE_MODULE_LINKER_FLAGS "${ARM_LINKER_FLAGS} ${CMAKE_MODULE_LINKER_FLAGS}")
set(CMAKE_EXE_LINKER_FLAGS "${ARM_LINKER_FLAGS} ${CMAKE_EXE_LINKER_FLAGS}")
else()
#message(WARNING "CMAKE_CXX_FLAGS='${CMAKE_CXX_FLAGS}' is defined")
endif()
if(USE_NEON)
message(WARNING "You use obsolete variable USE_NEON to enable NEON instruction set. Use -DENABLE_NEON=ON instead." )
set(ENABLE_NEON TRUE)
elseif(USE_VFPV3)
message(WARNING "You use obsolete variable USE_VFPV3 to enable VFPV3 instruction set. Use -DENABLE_VFPV3=ON instead." )
set(ENABLE_VFPV3 TRUE)
endif()
set(CMAKE_FIND_ROOT_PATH ${CMAKE_FIND_ROOT_PATH} ${ARM_LINUX_SYSROOT})
if(EXISTS ${CUDA_TOOLKIT_ROOT_DIR})
set(CMAKE_FIND_ROOT_PATH ${CMAKE_FIND_ROOT_PATH} ${CUDA_TOOLKIT_ROOT_DIR})
endif()
set(TOOLCHAIN_CONFIG_VARS ${TOOLCHAIN_CONFIG_VARS}
ARM_LINUX_SYSROOT
ENABLE_NEON
ENABLE_VFPV3
CUDA_TOOLKIT_ROOT_DIR
)
toolchain_save_config()
但运行cmake命令后仍然有以下输出：
命令：
khadas@Khadas:~/Downloads/opencv/platforms/linux/build_hardfp$ cmake -DBUILD_SHARED_LIBRARY=OFF -DLAPACK_LIBRARIES=/usr/lib/liblapack.a -DOPENCV_EXTRA_MODULES_PATH=/home/khadas/Downloads/opencv_contrib/modules -DCMAKE_TOOLCHAIN_FILE=../arm-gnueabi.toolchain.cmake ../../..
输出：
-- General configuration for OpenCV 4.0.0-pre =====================================
-- Version control: 3.4.3-374-g475c775-dirty
--
-- Extra modules:
-- Location (extra): /home/khadas/Downloads/opencv_contrib/modules
-- Version control (extra): 3.4.3-93-g3054618
--
-- Platform:
-- Timestamp: 2018-09-24T09:23:39Z
-- Host: Linux 4.9.40 aarch64
-- Target: Linux 1 arm
-- CMake: 3.5.1
-- CMake generator: Unix Makefiles
-- CMake build tool: /usr/bin/make
-- Configuration: Release
--
-- CPU/HW features:
-- Baseline:
-- requested: DETECT
-- disabled: VFPV3 NEON
--
-- C/C++:
-- Built as dynamic libs?: YES
-- C++ Compiler: /usr/bin/arm-linux-gnueabi-g++ (ver 5.4.0)
-- C++ flags (Release): -mthumb -fdata-sections -Wa,--noexecstack -fsigned-char -Wno-psabi -fsigned-char -W -Wall -Werror=return-type -Werror=non-virtual-dtor -Werror=address -Werror=sequence-point -Wformat -Werror=format-security -Wmissing-declarations -Wundef -Winit-self -Wpointer-arith -Wshadow -Wsign-promo -Wuninitialized -Winit-self -Wsuggest-override -Wno-narrowing -Wno-delete-non-virtual-dtor -Wno-comment -fdiagnostics-show-option -pthread -fomit-frame-pointer -ffunction-sections -fdata-sections -mfp16-format=ieee -fvisibility=hidden -fvisibility-inlines-hidden -O3 -DNDEBUG -DNDEBUG
-- C++ flags (Debug): -mthumb -fdata-sections -Wa,--noexecstack -fsigned-char -Wno-psabi -fsigned-char -W -Wall -Werror=return-type -Werror=non-virtual-dtor -Werror=address -Werror=sequence-point -Wformat -Werror=format-security -Wmissing-declarations -Wundef -Winit-self -Wpointer-arith -Wshadow -Wsign-promo -Wuninitialized -Winit-self -Wsuggest-override -Wno-narrowing -Wno-delete-non-virtual-dtor -Wno-comment -fdiagnostics-show-option -pthread -fomit-frame-pointer -ffunction-sections -fdata-sections -mfp16-format=ieee -fvisibility=hidden -fvisibility-inlines-hidden -g -O0 -DDEBUG -D_DEBUG
-- C Compiler: /usr/bin/arm-linux-gnueabi-gcc
-- C flags (Release): -mthumb -fdata-sections -Wa,--noexecstack -fsigned-char -Wno-psabi -fsigned-char -W -Wall -Werror=return-type -Werror=non-virtual-dtor -Werror=address -Werror=sequence-point -Wformat -Werror=format-security -Wmissing-declarations -Wmissing-prototypes -Wstrict-prototypes -Wundef -Winit-self -Wpointer-arith -Wshadow -Wuninitialized -Winit-self -Wno-narrowing -Wno-comment -fdiagnostics-show-option -pthread -fomit-frame-pointer -ffunction-sections -fdata-sections -mfp16-format=ieee -fvisibility=hidden -O3 -DNDEBUG -DNDEBUG
-- C flags (Debug): -mthumb -fdata-sections -Wa,--noexecstack -fsigned-char -Wno-psabi -fsigned-char -W -Wall -Werror=return-type -Werror=non-virtual-dtor -Werror=address -Werror=sequence-point -Wformat -Werror=format-security -Wmissing-declarations -Wmissing-prototypes -Wstrict-prototypes -Wundef -Winit-self -Wpointer-arith -Wshadow -Wuninitialized -Winit-self -Wno-narrowing -Wno-comment -fdiagnostics-show-option -pthread -fomit-frame-pointer -ffunction-sections -fdata-sections -mfp16-format=ieee -fvisibility=hidden -g -O0 -DDEBUG -D_DEBUG
-- Linker flags (Release): -Wl,--fix-cortex-a8 -Wl,--no-undefined -Wl,--gc-sections -Wl,-z,noexecstack -Wl,-z,relro -Wl,-z,now
-- Linker flags (Debug): -Wl,--fix-cortex-a8 -Wl,--no-undefined -Wl,--gc-sections -Wl,-z,noexecstack -Wl,-z,relro -Wl,-z,now
-- ccache: NO
-- Precompiled headers: NO
-- Extra dependencies: dl m pthread rt
-- 3rdparty dependencies:
--
-- OpenCV modules:
-- To be built: aruco bgsegm bioinspired calib3d ccalib core datasets dnn dnn_objdetect dpm face features2d flann fuzzy hfs highgui img_hash imgcodecs imgproc java_bindings_generator line_descriptor ml objdetect optflow phase_unwrapping photo plot python_bindings_generator reg rgbd saliency shape stereo stitching structured_light superres surface_matching text tracking ts video videoio videostab xfeatures2d ximgproc xobjdetect xphoto
-- Disabled: js world
-- Disabled by dependency: -
-- Unavailable: cnn_3dobj cudaarithm cudabgsegm cudacodec cudafeatures2d cudafilters cudaimgproc cudalegacy cudaobjdetect cudaoptflow cudastereo cudawarping cudev cvv freetype hdf java matlab ovis python2 python3 sfm viz
-- Applications: tests perf_tests apps
-- Documentation: NO
-- Non-free algorithms: NO
--
-- GUI:
-- GTK+: NO
--
-- Media I/O:
-- ZLib: build (ver 1.2.11)
-- JPEG: libjpeg-turbo (ver 1.5.3-62)
-- WEBP: build (ver encoder: 0x020e)
-- PNG: build (ver 1.6.34)
-- TIFF: build (ver 42 - 4.0.9)
-- JPEG 2000: build (ver 1.900.1)
-- OpenEXR: build (ver 1.7.1)
-- HDR: YES
-- SUNRASTER: YES
-- PXM: YES
-- PFM: YES
--
-- Video I/O:
-- DC1394: NO
-- FFMPEG: NO
-- avcodec: NO
-- avformat: NO
-- avutil: NO
-- swscale: NO
-- avresample: NO
-- GStreamer: NO
-- libv4l/libv4l2: NO
-- v4l/v4l2: linux/videodev2.h
--
-- Parallel framework: pthreads
--
-- Trace: YES (built-in)
--
-- Other third-party libraries:
-- Lapack: NO
-- Custom HAL: YES (carotene (ver 0.0.1))
-- Protobuf: build (3.5.1)
--
-- OpenCL: YES (no extra features)
-- Include path: /home/khadas/Downloads/opencv/3rdparty/include/opencl/1.2
-- Link libraries: Dynamic load
--
-- Python (for build): /usr/bin/python2.7
--
-- Install to: /home/khadas/Downloads/opencv/platforms/linux/build_hardfp/install
-- -----------------------------------------------------------------
--
-- Configuring done
-- Generating done
请考虑 Opencv Models 下输出中的以下行：
-- Unavailable: cnn_3dobj cudaarithm cudabgsegm cudacodec cudafeatures2d cudafilters cudaimgproc cudalegacy cudaobjdetect cudaoptflow cudastereo cudawarping cudev cvv freetype hdf java matlab ovis python2 python3 sfm viz
提前致谢！
【问题讨论】：
-
显示工具链的其余部分。你在里面设置了sysroot吗？
-
@Tsyvarev 这是opencv为交叉编译提供的默认工具链，它将在几秒钟内编辑帖子以添加完整文件。
-
工具链将 arm sysroot 添加到
CMAKE_FIND_ROOT_PATH变量中，并且包含在工具链中的gnu.toolchain.cmake文件将 CMake 用于搜索事物（库、标题、程序） 仅在此变量中指定的目录下。这就是为什么找不到安装在主机中的 Java。您需要在 sysroot 下安装 Java，并设置JAVA_HOME变量来引用该安装。 （例如，当前设置的JAVA_HOME适合安装在<sysroot>/usr/lib/jvm/java-8-openjdk-arm64下。） -
好的，那么如何检查
在我的机器上代表什么剂量，我认为 /usr 是顶级目录 -
对不起，我不知道。您正在为您的目标机器进行交叉编译，看来您应该了解它的 sysroot。 （并且，可能应该提示工具链）。
标签： java c++ opencv cmake opencv3.0