Linuxgcc增加sysroot,c++交叉编译时CMAKE缺少sysroot

我在使用CMAKE设置交叉编译时遇到了一些麻烦。我正在使用的工具链是在yocto中创建的&＃xff0c;可以在cmake之外完美地工作。

我已经按照教程设置了以下工具链文件:SET(CMAKE_SYSTEM_NAME Linux)

SET(CMAKE_SYSTEM_VERSION 1)

SET(CMAKE_SYSTEM_PROCESSOR arm)

# specify the cross compiler

SET(tools /opt/poky/1.7.1/sysroots/x86_64-pokysdk-linux/usr)

SET(CMAKE_C_COMPILER ${tools}/bin/arm-poky-linux-gnueabi/arm-poky-linux-gnueabi-gcc)

SET(CMAKE_CXX_COMPILER ${tools}/bin/arm-poky-linux-gnueabi/arm-poky-linux-gnueabi-gcc)

# set sysroot

SET(CMAKE_SYSROOT /home/sifu/test-yocto/qemuarmdfs)

#SET(CMAKE_FIND_ROOT_PATH /home/sifu/test-yocto/qemuarm)

# search for programs in the build host directories

SET(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM NEVER)

# for libraries and headers in the target directories

SET(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY)

SET(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY)

SET(CMAKE_FIND_ROOT_PATH_MODE_PACKAGE ONLY)

并在运行cmake时得到以下错误

The C compiler

"/opt/poky/1.7.1/sysroots/x86_64-pokysdk-linux/usr/bin/arm-poky-linux-gnueabi/arm-poky-linux-gnueabi-gcc"

is not able to compile a simple test program.

It fails with the following output:

Change Dir: /home/sifu/Projects/mv/doublepump-single-pump-sw.ss016m21_swapp/cc/CMakeFiles/CMakeTmp

Run Build Command:/usr/bin/make "cmTryCompileExec4012536451/fast"

/usr/bin/make -f CMakeFiles/cmTryCompileExec4012536451.dir/build.make

CMakeFiles/cmTryCompileExec4012536451.dir/build

make[1]: Entering directory

&＃96;/home/sifu/Projects/mv/doublepump-single-pump-sw.ss016m21_swapp/cc/CMakeFiles/CMakeTmp&＃39;

/usr/bin/cmake -E cmake_progress_report

/home/sifu/Projects/mv/doublepump-single-pump-sw.ss016m21_swapp/cc/CMakeFiles/CMakeTmp/CMakeFiles

1

Building C object

CMakeFiles/cmTryCompileExec4012536451.dir/testCCompiler.c.o

/opt/poky/1.7.1/sysroots/x86_64-pokysdk-linux/usr/bin/arm-poky-linux-gnueabi/arm-poky-linux-gnueabi-gcc

-O2 -pipe -g -feliminate-unused-debug-types -o

CMakeFiles/cmTryCompileExec4012536451.dir/testCCompiler.c.o -c

/home/sifu/Projects/mv/doublepump-single-pump-sw.ss016m21_swapp/cc/CMakeFiles/CMakeTmp/testCCompiler.c

Linking C executable cmTryCompileExec4012536451

/usr/bin/cmake -E cmake_link_script

CMakeFiles/cmTryCompileExec4012536451.dir/link.txt --verbose&＃61;1

/opt/poky/1.7.1/sysroots/x86_64-pokysdk-linux/usr/bin/arm-poky-linux-gnueabi/arm-poky-linux-gnueabi-gcc

-O2 -pipe -g -feliminate-unused-debug-types -Wl,-O1 -Wl,--hash-style&＃61;gnu

-Wl,--as-needed CMakeFiles/cmTryCompileExec4012536451.dir/testCCompiler.c.o

-o cmTryCompileExec4012536451 -rdynamic

... (A lot of ld errors similar to the one below)

/opt/poky/1.7.1/sysroots/x86_64-pokysdk-linux/usr/libexec/arm-poky-linux-gnueabi/gcc/arm-poky-linux-gnueabi/4.9.1/ld:

cannot find crtn.o: No such file or directory

collect2: error: ld returned 1 exit status

make[1]: Leaving directory

&＃96;/home/sifu/Projects/mv/doublepump-single-pump-sw.ss016m21_swapp/cc/CMakeFiles/CMakeTmp&＃39;

如果我使用--sysroot &＃61;/home/sifu/test-yocto/qemuarmdfs手动运行上面日志中描述的gcc命令&＃xff0c;它对我有用。当在工具链文件中添加sysroot的路径时&＃xff0c;为什么不使用sysroot标志进行cmake。

最佳答案

我对此问题有两种解决方案:

我在工具链文件中使用以下代码:

# compiler

set(CMAKE_C_COMPILER /path/to/arm-none-linux-gnueabi-gcc)

set(CMAKE_CXX_COMPILER /path/to/arm-none-linux-gnueabi-g&＃43;&＃43;)

# sysroot location

set(MYSYSROOT /path/to/sysroots/cortexa7-vfp-neon-telechips-linux-gnueabi)

# compiler/linker flags

set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} --sysroot&＃61;${MYSYSROOT}" CACHE INTERNAL "" FORCE)

set(CMAKE_C_LINK_FLAGS "${CMAKE_C_LINK_FLAGS} --sysroot&＃61;${MYSYSROOT}" CACHE INTERNAL "" FORCE)

set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} --sysroot&＃61;${MYSYSROOT}" CACHE INTERNAL "" FORCE)

set(CMAKE_CXX_LINK_FLAGS "${CMAKE_CXX_LINK_FLAGS} --sysroot&＃61;${MYSYSROOT}" CACHE INTERNAL "" FORCE)

# cmake built-in settings to use find_xxx() functions

set(CMAKE_FIND_ROOT_PATH "${MYSYSROOT}")

set(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM NEVER)

set(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY)

set(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY)

第二种解决方案是在工具链文件中使用CMakeForceCompiler软件包。看起来不同&＃xff0c;但是我有相同的结果:

# compiler

include(CMakeForceCompiler)

cmake_force_c_compiler(/path/to/arm-none-linux-gnueabi-gcc GNU)

cmake_force_cxx_compiler(/path/to/arm-none-linux-gnueabi-g&＃43;&＃43; GNU)

# sysroot location

set(MYSYSROOT /path/to/sysroots/cortexa7-vfp-neon-telechips-linux-gnueabi)

# compiler/linker flags

add_definitions("--sysroot&＃61;${MYSYSROOT}")

set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} --sysroot&＃61;${MYSYSROOT}" CACHE INTERNAL "" FORCE)

set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} --sysroot&＃61;${MYSYSROOT}" CACHE INTERNAL "" FORCE)

# cmake built-in settings to use find_xxx() functions

set(CMAKE_FIND_ROOT_PATH ${MYSYSROOT})

set(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM NEVER)

set(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY)

set(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY)

顺便说一句&＃xff0c;我不能使用CMAKE_SYSROOT变量&＃xff0c;因为它仅从CMake v3.0起可用。