Official STM32 showing many undeclared identifiers for blink sketch but compiles ok

[toogooda]

Describe the bug
LED_BUILTIN, HIGH, delay, OUTPUT all underlined in red and showing "Use of undeclared identifier". Strangely digitalWrite and pinMode are recognised OK.
If you ignore and compile it completes without exception.

To Reproduce
Steps to reproduce the behavior:

1. Add additional boards URL "https://github.com/stm32duino/BoardManagerFiles/raw/master/STM32/package_stm_index.json"
2. Select Blink example
3. Select any STM board I used STM32F103RC

Screenshots

Desktop (please complete the following information):

• Windows 10

Additional context
There are other issue with STM boards that I will log separately.

[toogooda]

It is also inconsistent in that the same variable can be used twice, once recognised and once unidentified. see image and delay examples:

[ubidefeo]

@toogooda
sometimes the definition of macros from 3rd party cores doesn't play well with the Language Server.
You can see that digitalWrite and pinMode behave correctly.

The LS is still in an early stage of refinement, and it's being actively worked on.
Bare with us

For now I'm assigning this a lower priority
thanks

[toogooda]

@toogooda
sometimes the definition of macros from 3rd party cores doesn't play well with the Language Server.
You can see that digitalWrite and pinMode behave correctly.

The LS is still in an early stage of refinement, and it's being actively worked on.
Bare with us

For now I'm assigning this a lower priority
thanks

No problem, happy to do what testing needs doing for STM32.

[ag88]

i'd like to provide a little more info on this topic, i turned on (File > preferences) language server logging
in /tmp/arduino-language-server991402071 i found
build.options.json

{
  "additionalFiles": "",
  "builtInLibrariesFolders": "",
  "builtInToolsFolders": "",
  "compiler.optimization_flags": "",
  "customBuildProperties": "build.warn_data_percentage=75",
  "fqbn": "STM32:stm32:GenF4",
  "hardwareFolders": "/home/user/.arduino15/packages",
  "otherLibrariesFolders": "/home/user/Arduino/libraries",
  "runtime.ide.version": "10607",
  "sketchLocation": "/home/user/Arduino/sketch_mar28a/sketch_mar28a.ino"
}

includes.cache

[
  {
    "Sourcefile": null,
    "Include": "",
    "Includepath": "/opt1/arduino/dotarduino15/packages/STM32/hardware/stm32/1.9.0/cores/arduino"
  },
  {
    "Sourcefile": null,
    "Include": "",
    "Includepath": "/opt1/arduino/dotarduino15/packages/STM32/hardware/stm32/1.9.0/variants/BLACK_F407XX"
  },
  {
    "Sourcefile": "/tmp/arduino-language-server991402071/sketch/sketch_mar28a.ino.cpp",
    "Include": "",
    "Includepath": null
  }
]

^^^ the path of the core is correctly inferred, but that there is sub-directories with more include and c files
the include path for the variant is incorrect and the source files given as null, and includes given as ""
i'd think many paths are actually missing

preproc/ folder empty
sketch/ folder has the correct sketch

[ag88]

couldn't really figure out how
vscode-arduino-tools
arduino-language-server
works in IDE 2.0, it seem to be calling clangd, but it is difficult to figure out how the relevant directories and files are passed
i'm halfway wondering if precompiled clangd indexes may help
https://clangd.llvm.org/design/indexing.html
a trouble is os specific path/folder/file access may need to be dealt with.

[ubidefeo]

@ag88
our language server does use Clangd and is currently actively being developed for Arduino IDE 2.0
Refinements to how it behaves inside VSCode might come in the future, but for now we do not provide official support for VS Code

[ag88]

one more observation as i'm trying to figure out the root cause
compile_commands.json

[]

pretty much an empty file
the specs for that seem to be here
https://clang.llvm.org/docs/JSONCompilationDatabase.html
perhaps i'd try to define a compile_commands.json manually and try the autocomplete again?

apparently clangd does some form of 'background indexing'
accordingly compile_commands.json is needed
https://clangd.llvm.org/installation.html

any hints on how to go about with this? e.g. should i replace that in
arduino-language-server5444..../compile_commands.json
and restart the IDE?

part of the manal troubleshooting logs followed up in this thread
https://forum.arduino.cc/index.php?topic=734627.msg4942746#msg4942746

[ag88]

the language server toolchain architecture apparently seem to be
arduino-ide2 -> vscode-arduino-tools (module) -> arduino-language-server -> clangd
in inols-err.log

--> initialize(file:///home/user/Arduino/sketch_mar28b)
running:  /opt1/arduino/arduino-ide_2.0.0-beta.4-snapshot.51195eb_Linux_64bit/resources/app/node_modules/arduino-ide-extension/build/arduino-cli compile --fqbn STM32:stm32:GenF4 --only-compilation-database --clean --source-override /tmp/071191930 --build-path /tmp/arduino-language-server071191930 --format json /home/user/Arduino/sketch_mar28b

hence compile_commands.json is actually generated by arduino-cli using the --only-compilation-database option

i went into /tmp/arduino-language-server071191930 and tried

/opt1/arduino/arduino-ide_2.0.0-beta.4-snapshot.51195eb_Linux_64bit/resources/app/node_modules/arduino-ide-extension/build/arduino-cli compile --fqbn STM32:stm32:GenF4 --only-compilation-database --clean --build-path . --format json /home/user/Arduino/sketch_mar28b
{
  "compiler_out": "",
  "compiler_err": "arm-none-eabi-g++: error: ./sketch/build_opt.h: No such file or directory\n",
  "builder_result": {
    "build_path": "."
  },
  "success": false
}

^^^ in running the above command i've removed the source override option and did the compilation in the /tmp/arduino-language-server071191930 directory

however if I remove --only-compilation-database option the build completes, though with a success : false status

/opt1/arduino/arduino-ide_2.0.0-beta.4-snapshot.51195eb_Linux_64bit/resources/app/node_modules/arduino-ide-extension/build/arduino-cli compile --fqbn STM32:stm32:GenF4 --clean --build-path . --format json /home/user/Arduino/sketch_mar28b{
  "compiler_out": "Couldn't deeply cache core build: Rel: can't make . relative to /tmp/arduino-core-cache\nRunning normal build of the core...\n",
  "compiler_err": "",
  "builder_result": {
    "build_path": "."
  },
  "success": false
}

and it successfully generates a compile_commands.json

[
 {
  "directory": "/tmp/arduino-language-server071191930",
  "arguments": [
   "/opt1/arduino/dotarduino15/packages/STM32/tools/xpack-arm-none-eabi-gcc/9.2.1-1.1/bin/arm-none-eabi-g++",
   "-mcpu=cortex-m4",
   "-mfpu=fpv4-sp-d16",
   "-mfloat-abi=hard",
   "-mthumb",
   "@./sketch/build_opt.h",
   "-c",
   "-Os",
   "-w",
   "-std=gnu++14",
   "-ffunction-sections",
   "-fdata-sections",
   "-nostdlib",
   "-fno-threadsafe-statics",
   "--param",
   "max-inline-insns-single=500",
   "-fno-rtti",
   "-fno-exceptions",
   "-fno-use-cxa-atexit",
   "-MMD",
   "-I/home/user/Arduino/sketch_mar28b",
   "-I/opt1/arduino/dotarduino15/packages/STM32/hardware/stm32/1.9.0/cores/arduino/avr",
   "-I/opt1/arduino/dotarduino15/packages/STM32/hardware/stm32/1.9.0/cores/arduino/stm32",
   "-I/opt1/arduino/dotarduino15/packages/STM32/hardware/stm32/1.9.0/cores/arduino/stm32/LL",
   "-I/opt1/arduino/dotarduino15/packages/STM32/hardware/stm32/1.9.0/cores/arduino/stm32/usb",
   "-I/opt1/arduino/dotarduino15/packages/STM32/hardware/stm32/1.9.0/cores/arduino/stm32/OpenAMP",
...

[utherbone]

Additional info for this bug
Similar to: #291 and archived repo: arduino/arduino-pro-ide#244

board to STM32
Screenshots

If change to board AVR nano shows this:

Additional context
I searched here did not find much about the new updates I hope have helped. sharing what happened

Distribution

• OS: Ubuntu
• Version: 20.04.2 LTS
  Kernel
• kernel: Linux
• Version: 5.4.0-73-generic