断言失败:工具链无法生成伪C文件

Question

许多学生和我自己一直在尝试在Windows 10下建立Zephyr RTOS构建环境，以构建针对各种ARM Cortex M板的应用程序。我们每个人都遵循了"西风"；《入门指南》；遇到了同样的问题。当为许多不同的板编译时(让我们只使用nrf52840dk_nrf52840作为示例(，我们会得到以下错误：

错误消息

C:UsersJohncodeeip-zephyr>west build -p auto -b nrf52840dk_nrf52840 .zephyrsamplesbasicblinky
-- west build: generating a build system
Including boilerplate (Zephyr base): C:/Users/John/code/eip-zephyr/zephyr/cmake/app/boilerplate.cmake
-- Application: C:/Users/John/code/eip-zephyr/zephyr/samples/basic/blinky
-- Zephyr version: 2.4.0 (C:/Users/John/code/eip-zephyr/zephyr)
-- Found Python3: C:/Python39/python.exe (found suitable exact version "3.9.0") found components: Interpreter
-- Found west (found suitable version "0.8.0", minimum required is "0.7.1")
-- Board: nrf52840dk_nrf52840
-- Cache files will be written to: C:/Users/John/code/eip-zephyr/zephyr/.cache
-- Found toolchain: gnuarmemb (C:/gnu_arm_embedded)
-- Found BOARD.dts: C:/Users/John/code/eip-zephyr/zephyr/boards/arm/nrf52840dk_nrf52840/nrf52840dk_nrf52840.dts
-- Generated zephyr.dts: C:/Users/John/code/eip-zephyr/build/nrf52840dk_nrf52840/blinky/zephyr/zephyr.dts
-- Generated devicetree_unfixed.h: C:/Users/John/code/eip-zephyr/build/nrf52840dk_nrf52840/blinky/zephyr/include/generated/devicetree_unfixed.h
Parsing C:/Users/John/code/eip-zephyr/zephyr/Kconfig
Loaded configuration 'C:/Users/John/code/eip-zephyr/zephyr/boards/arm/nrf52840dk_nrf52840/nrf52840dk_nrf52840_defconfig'
Merged configuration 'C:/Users/John/code/eip-zephyr/zephyr/samples/basic/blinky/prj.conf'
Configuration saved to 'C:/Users/John/code/eip-zephyr/build/nrf52840dk_nrf52840/blinky/zephyr/.config'
Kconfig header saved to 'C:/Users/John/code/eip-zephyr/build/nrf52840dk_nrf52840/blinky/zephyr/include/generated/autoconf.h'
-- The C compiler identification is GNU 9.3.1
-- The CXX compiler identification is GNU 9.3.1
-- The ASM compiler identification is GNU
-- Found assembler: C:/gnu_arm_embedded/bin/arm-none-eabi-gcc.exe
CMake Error at ../../../cmake/extensions.cmake:1569 (message):
Assertion failed: The toolchain is unable to build a dummy C file.  See
CMakeError.log.
Call Stack (most recent call first):
../../../CMakeLists.txt:42 (assert)

-- Configuring incomplete, errors occurred!
See also "C:/Users/John/code/eip-zephyr/build/nrf52840dk_nrf52840/blinky/CMakeFiles/CMakeOutput.log".
See also "C:/Users/John/code/eip-zephyr/build/nrf52840dk_nrf52840/blinky/CMakeFiles/CMakeError.log".
FATAL ERROR: command exited with status 1: 'C:Program FilesCMakebincmake.EXE' '-DWEST_PYTHON=c:python39python.exe' '-BC:UsersJohncodeeip-zephyrbuildnrf52840dk_nrf52840blinky' '-SC:UsersJohncodeeip-zephyrzephyrsamplesbasicblinky' -GNinja -DBOARD=nrf52840dk_nrf52840

此错误将我们引向以下文件：CMakeError和CMakeOutput。以下是它们的内容：

CMakeError

Compiling the C compiler identification source file "CMakeCCompilerId.c" failed.
Compiler: C:/gnu_arm_embedded/bin/arm-none-eabi-gcc.exe 
Build flags: 
Id flags:  
The output was:
1
c:/gnu_arm_embedded/bin/../lib/gcc/arm-none-eabi/9.3.1/../../../../arm-none-eabi/bin/ld.exe: c:/gnu_arm_embedded/bin/../lib/gcc/arm-none-eabi/9.3.1/../../../../arm-none-eabi/liblibc.a(lib_a-exit.o): in function `exit':
exit.c:(.text.exit+0x2c): undefined reference to `_exit'
collect2.exe: error: ld returned 1 exit status

Compiling the CXX compiler identification source file "CMakeCXXCompilerId.cpp" failed.
Compiler: C:/gnu_arm_embedded/bin/arm-none-eabi-gcc.exe 
Build flags: 
Id flags:  
The output was:
1
c:/gnu_arm_embedded/bin/../lib/gcc/arm-none-eabi/9.3.1/../../../../arm-none-eabi/bin/ld.exe: c:/gnu_arm_embedded/bin/../lib/gcc/arm-none-eabi/9.3.1/../../../../arm-none-eabi/liblibc.a(lib_a-exit.o): in function `exit':
exit.c:(.text.exit+0x2c): undefined reference to `_exit'
collect2.exe: error: ld returned 1 exit status

CMakeOutput

The target system is: Generic - 2.4.0 - arm
The host system is: Windows - 10.0.19041 - AMD64
Compiling the C compiler identification source file "CMakeCCompilerId.c" succeeded.
Compiler: C:/gnu_arm_embedded/bin/arm-none-eabi-gcc.exe 
Build flags: 
Id flags: -c 
The output was:
0

Compilation of the C compiler identification source "CMakeCCompilerId.c" produced "CMakeCCompilerId.o"
The C compiler identification is GNU, found in "C:/Users/John/code/eip-zephyr/build/nrf52840dk_nrf52840/blinky/CMakeFiles/3.19.0/CompilerIdC/CMakeCCompilerId.o"
Compiling the CXX compiler identification source file "CMakeCXXCompilerId.cpp" succeeded.
Compiler: C:/gnu_arm_embedded/bin/arm-none-eabi-gcc.exe 
Build flags: 
Id flags: -c 
The output was:
0

Compilation of the CXX compiler identification source "CMakeCXXCompilerId.cpp" produced "CMakeCXXCompilerId.o"
The CXX compiler identification is GNU, found in "C:/Users/John/code/eip-zephyr/build/nrf52840dk_nrf52840/blinky/CMakeFiles/3.19.0/CompilerIdCXX/CMakeCXXCompilerId.o"
Checking whether the ASM compiler is GNU using "--version" matched "(GNU assembler)|(GCC)|(Free Software Foundation)":
arm-none-eabi-gcc.exe (GNU Arm Embedded Toolchain 9-2020-q2-update) 9.3.1 20200408 (release)
Copyright (C) 2019 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

我的问题：

1. 这个错误是什么意思
2. 如何修复它，以便成功构建应用程序

Answer 1

在zephyr rtos slack通道中进行了一些挖掘并得到了其他人的帮助后，我发现其他人也遇到了同样的问题，所以我将在这里发布我的修复程序，希望它也能解决其他人的问题。

解决办法有两个：

1. 您必须从CMake 3.19降级。这项工作之前的大多数版本，但3.17.2是推荐的版本。如果您使用的是windows，则可以使用chocolatey命令：choco install cmake --installargs 'ADD_CMAKE_TO_PATH=System' --version 3.17.2 --allow-downgrade --force来完成此操作
2. 您必须删除.cache文件夹。您以前的生成输出告诉您将存储这些内容的位置。这句话的开头是这样的："——缓存文件也将被写入：">

我仍然不知道为什么会抛出这个错误，也不知道应该做些什么来永久修复它，但这是目前的修复方法。

Answer 2

我只想通知您，Zephyr存储库中目前正在进行一个变通方法。看看这里：https://github.com/zephyrproject-rtos/zephyr/pull/30272