如何在CMake中追踪丢失的变量值?

时间:2017-04-30 16:13:01

标签: variables cmake trace fedora-25

修改:接受的答案尚未解决我的问题,但它回答了我问过的问题 - 如果您可以帮我解决下面描述的实际问题,您可以回答this问题

我有一个CMake项目,该项目使用需要设置变量的框架(即https://github.com/queezythegreat/arduino-cmake,需要ARDUINO_SDK_PATH

奇怪的是,在命令行上设置该变量之后,它首先有一个值,但看起来它会在一段时间后消失。

我正在运行

cmake -DARDUINO_SDK_PATH=/path/to/sdk ..

..并收到一条错误消息,告诉我它没有设置。打印出CMakeLists.txt顶部的值,并在这个检查变量的框架深处,给出了类似这样的信息:

>>> ARDUINO_SDK_PATH (beginning): '/home/me/project/arduino-1.8.2'
>>> ARDUINO_SDK_PATH (before check): '/home/me/project/arduino-1.8.2'
-- The C compiler identification is GNU 6.2.0
-- The CXX compiler identification is GNU 6.2.0
-- Check for working C compiler: /usr/bin/avr-gcc
>>> ARDUINO_SDK_PATH (before check): ''
CMake Error at /home/me/project/arduino-cmake/cmake/ArduinoToolchain.cmake:84 (message):
  Could not find Arduino SDK (set ARDUINO_SDK_PATH)!
Call Stack (most recent call first):
  /home/me/project/build/CMakeFiles/3.6.2/CMakeSystem.cmake:6 (include)
  /home/me/project/build/CMakeFiles/CMakeTmp/CMakeLists.txt:3 (project)

CMake Error: Internal CMake error, TryCompile configure of cmake failed
-- Configuring incomplete, errors occurred!
See also "/home/me/project/build/CMakeFiles/CMakeOutput.log".

所以看起来ARDUINO_SDK_PATH以某种方式失去了它的价值。我没有找到一个实际的命令,它被分配了任何值,所以我不知道如何继续..我现在可以在任何地方向我的CMake项目添加代码以打印出ARDUINO_SDK_PATH的值但是我想知道是否有内置的方法来跟踪变量值。

我尝试cmake --trace ..cmake --trace-expand ..,但输出似乎没有帮助..

系统:带有CMake 3.6.2的Fedora 25

更新

感谢Florian我已将variable_watch(ARDUINO_SDK_PATH)添加为CMakeLists.txt中的第一行,现在我的变量跟踪行(message())如下所示:

CMake Debug Log at arduino-cmake/cmake/ArduinoToolchain.cmake:41 (MESSAGE):
  Variable "ARDUINO_SDK_PATH" was accessed using READ_ACCESS with value
  "/home/me/project/arduino-1.8.2".
Call Stack (most recent call first):
  /usr/share/cmake/Modules/CMakeDetermineSystem.cmake:98 (include)
  CMakeLists.txt:10 (project)

>>> ARDUINO_SDK_PATH (before check): /home/me/project/arduino-1.8.2

我有大约30条这样的消息,但是有一些跟踪线没有值和没有跟踪消息。

所以看起来变量ARDUINO_SDK_PATH被一个新的替换,它是空的并且不再被跟踪..

重现

为了使此行为可重现,我上传了代码:https://github.com/frans-fuerst/trinket_led

注意:提供的CMakeLists.txt尚未包含有用的代码 - 它只是重现错误。

您需要下载Arduino-SDK,将其解压缩并在命令行中提供路径:

tar xvf ~/Downloads/arduino-1.8.2-linux64.tar.xz 
git clone https://github.com/frans-fuerst/trinket_led
cd trinket_led
git submodules update --init
mkdir build
cd build
cmake -DARDUINO_SDK_PATH=/path/to/arduino-1.8.2 ..

注意:find_path中的ArduinoToolchain.cmake命令看起来很可疑。但你可以用相同的结果删除它..

CMakeFiles / CMakeOutput.log

The target system is: Arduino -  - 
The host system is: Linux - 4.10.12-200.fc25.x86_64+debug - x86_64
Compiling the C compiler identification source file "CMakeCCompilerId.c" succeeded.
Compiler: /usr/bin/avr-gcc 
Build flags: 
Id flags: 

The output was:
0


Compilation of the C compiler identification source "CMakeCCompilerId.c" produced "a.out"

The C compiler identification is GNU, found in "/home/frans/_HOME/1704_trinket_led/build/CMakeFiles/3.6.2/CompilerIdC/a.out"

Compiling the CXX compiler identification source file "CMakeCXXCompilerId.cpp" succeeded.
Compiler: /usr/bin/avr-g++ 
Build flags: 
Id flags: 

The output was:
0


Compilation of the CXX compiler identification source "CMakeCXXCompilerId.cpp" produced "a.out"

The CXX compiler identification is GNU, found in "/home/frans/_HOME/1704_trinket_led/build/CMakeFiles/3.6.2/CompilerIdCXX/a.out"

1 个答案:

答案 0 :(得分:3)

只需将variable_watch(ARDUINO_SDK_PATH)放在CMakeLists.txt的顶部。

<强>参考