Using Kconfig options in manifest file (PACMAN-1238)

[roma-jam]

The Component Manager version

2.4.6

ESP-IDF Version

6.0

python Version

3.12.3

Operating System

Ubuntu 24.04

Browser (for https://components.espressif.com Issues)

No response

Description

Hi dear idf-compoment-manager Team,

I am trying to build the chain of idf-components with Kconfig parameter usage.

My approach was based on the description here, case 3:

dependencies:
   espressif/mdns:
      version: "1.8.1"

   example/cmp:
     version: "*"
     matches:
       - if: "$CONFIG{MDNS_MAX_SERVICES} == 10"

My potential setup:

• top-level idf component esp-usb-wrp, that will provide public API for USB
• second-level idf component esp-usb-backend, that should: fetch a component (tinyusb or cherryusb) based on the Kconfig parameter, provide the backend-specific api to esp-usb-wrp and interact with target-backend.

Why two of them, not one?
Because I expect the dependency pattern to work in my case when I am trying to build the example:

dependencies:
  roma-jam/esp-usb-wrp:
    version: "*"
    pre_release: true

  roma-jam/esp-usb-backend:
    version: "*"
    pre_release: true

But, obviously it is not working, that is why I decided to open the issue.

The current problem is that I am not able to get rid of the message during the config:

NOTICE: Processing 3 dependencies:
NOTICE: [1/3] roma-jam/esp-usb-backend (0.0.1-rc0) (/home/roman/workspace/Private/esp-usb-backend)
NOTICE: [2/3] roma-jam/esp-usb-wrp (0.0.1-beta0) (/home/roman/workspace/Private/esp-usb-wrp)
NOTICE: [3/3] idf (6.0.0)
CMake Warning at /home/roman/workspace/Espressif/github/esp-idf/tools/cmake/build.cmake:691 (message):
  WARNING: The following Kconfig variables were used in "if" clauses, but not
  found in any Kconfig file:

      ESP_USB_BACKEND_CHERRYUSB, introduced by cherry-embedded/cherryusb, defined in /home/roman/workspace/Private/esp-usb-backend/idf_component.yml
      ESP_USB_BACKEND_TINYUSB, introduced by roma-jam/tinyusb, defined in /home/roman/workspace/Private/esp-usb-backend/idf_component.yml

I am not sure that it is an issue, but the questions are:

1. Am I able to use Kconfig and is it possible to use matches: - if: "$CONFIG{... in my case inside the second-level idf component? Or it is possible, only when they are present in the application manifest?
2. Will/Should that work during overriding the path, because obviously I have to do that to try it out locally.

Sorry if I am missing something and thanks in advance.

To Reproduce

I don't know any example of that, but it is possible to create two components, where: 

1. component1: has a dependency from component2 and introduce the Kconfig parameters.
2. component2: has an optional dependency from component, which will be mapped via component1 config

Try to configure that with overriding_path.

Expected behaviour

Create a dependency and fetch different components, based on Kconfig parameter.

Additional info

No response

I have checked existing issues and online Documentation

• I confirm I have checked existing issues and online Documentation.

[XDanielPaul]

Hello @roma-jam!

Thanks for reaching out!
In short I believe that the answer to both of your questions is true. You should be able to use KConfig Options in esp-usb-backend as the component is the direct dependency of the project.

From docs:

Only Kconfig options defined in the ESP-IDF project or its direct dependency components are supported

Regarding override_path this should work as well

I could not reproduce your problem and would like you to clarify, where did you define your KConfig file and what is the content

[roma-jam]

Hi @XDanielPaul,

thanks for the response.

I believe that the answer to both of your questions is true.

Cool, good to know at least that it is doable.

Based on the idea, I have a top component (assume the component name is wrapper) which introduces the Kconfig parameters: CONFIG_BACKEND_ONE and GONFIG_BACKEND_TWO. So, it has Kconfig file in the root folder and the following manifest:

description: wrapper
version: "0.0.1"

dependencies:
  roma-jam/backend_comp:
    version: "*" 

The next component that actually uses the backend components directly (assume they are backend1 and backend2) is called backend_selector. It doesn't have Kconfig and has the following manifest file:

description: backend_selector
version: "0.0.1"

dependencies:
  roma-jam/backend1:
    version: "*"
    matches:
      - if: "$CONFIG{BACKEND_ONE} == True"

  roma-jam/backend2:
    version: "*"
    matches:
      - if: "$CONFIG{BACKEND_TWO} == True"

I assume, that configuration of the application with the following manifest:

dependencies:
  roma-jam/wrapper:
    version: "*"
    
  roma-jam/backend_selector:
    version: "*"

should solve the Kconfig dependencies correctly, because they (Kconfig parameters) defined in its direct dependency component (wrapper).

Am I right or missing something?

So, probably the main question is:

1. Do I need to have the backend_comp as a dependency for wrapper component? Because it seems that exactly it breaks the logic and causes my problem.

And, as a follow-up:
2. Is it necessary in my case to provide it's dependency in component manifest? Maybe, having two of them in the application manifest is enough.

Thanks for the response and appreciate any hints.

[XDanielPaul]

Hello @roma-jam,

You are correct with your assumptions.

To answer your questions:

1. You do not have to have backend component as a dependency for wrapper (I don't think it matters/breaks/fixes anything in this particular case)
2. I am sorry if I missunderstood your question, but I will make assumptions on:

• "it's" means backend_comp
• "component manifest" means wrapper component
• "two of them" means wrapper and backend_selector in the configuration of the application

If this holds, then the answer is that having the backend and wrapper in the project manifest is enough.

Based on your description I have created an example which worked for me. I would like to ask if this example covers your use case and if you experience any errors with the following.

Structure:

.
├── app
│   ├── CMakeLists.txt
│   └── main
│       ├── CMakeLists.txt
│       ├── idf_component.yml
│       └── main.c
├── esp-usb-backend
│   ├── CMakeLists.txt
│   ├── backend.c
│   └── idf_component.yml
└── esp-usb-wrp
   ├── CMakeLists.txt
   ├── Kconfig
   ├── idf_component.yml
   └── wrapper.c

App requires wrapper and backend (they will eventually be in the registry and you need to work with them locally - so override_path).

app/main/idf_component.yml

version: "0.0.1"
dependencies:
  esp-usb-wrp:
    override_path: ../../esp-usb-wrp
  esp-usb-backend:
    override_path: ../../esp-usb-backend

Wrapper component requires esp-usb-backend and provides the KConfig values (Tested this even without including esp-usb-backend as a dependency - still works)

esp-usb-wrp/idf_component.yml

version: "0.0.1"
dependencies:
  esp-usb-backend:
    override_path: ../esp-usb-backend/

esp-usb-wrp/KConfig

config ESP_USB_BACKEND_CHERRYUSB
    bool "Enable cherry"
    default y

config ESP_USB_BACKEND_TINYUSB
    bool "Enable tiny"
    default n

Backend component defines components which require Kconfig options (I used registry components)

esp-usb-backend/idf_component.yml

version: "0.0.1"
dependencies:
  roma-jam/tinyusb:
    version: "*"
    matches:
      - if: "$CONFIG{ESP_USB_BACKEND_TINYUSB} == True"
  cherry-embedded/cherryusb:
    version: "1.5.2~2"
    matches:
      - if: "$CONFIG{ESP_USB_BACKEND_CHERRYUSB} == True"

So, with this configuration. When I run idf.py set-target esp32p4 (cherryusb requires either S2/S3/P4 target) I get following:

> idf.py set-target esp32p4
Adding "set-target"'s dependency "fullclean" to list of commands with default set of options.
Executing action: fullclean
Build directory '/Users/danielpaul/work/cm_testing/esp_usb_kconfig_repro/app/build' not found. Nothing to clean.
Executing action: set-target
Set Target to: esp32p4, new sdkconfig will be created.
Running cmake in directory /Users/danielpaul/work/cm_testing/esp_usb_kconfig_repro/app/build
Executing "cmake -G 'Unix Makefiles' -DPYTHON_DEPS_CHECKED=1 -DPYTHON=/Users/danielpaul/.espressif/python_env/idf5.5_py3.13_env/bin/python -DESP_PLATFORM=1 -DIDF_TARGET=esp32p4 -DCCACHE_ENABLE=0 /Users/danielpaul/work/cm_testing/esp_usb_kconfig_repro/app"...
-- Found Git: /opt/homebrew/bin/git (found version "2.51.2")
-- Minimal build - OFF
-- The C compiler identification is GNU 14.2.0
-- The CXX compiler identification is GNU 14.2.0
-- The ASM compiler identification is GNU
-- Found assembler: /Users/danielpaul/.espressif/tools/riscv32-esp-elf/esp-14.2.0_20251107/riscv32-esp-elf/bin/riscv32-esp-elf-gcc
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Check for working C compiler: /Users/danielpaul/.espressif/tools/riscv32-esp-elf/esp-14.2.0_20251107/riscv32-esp-elf/bin/riscv32-esp-elf-gcc - skipped
-- Detecting C compile features
-- Detecting C compile features - done
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Check for working CXX compiler: /Users/danielpaul/.espressif/tools/riscv32-esp-elf/esp-14.2.0_20251107/riscv32-esp-elf/bin/riscv32-esp-elf-g++ - skipped
-- Detecting CXX compile features
-- Detecting CXX compile features - done
-- git rev-parse returned 'fatal: not a git repository (or any of the parent directories): .git'
-- Could not use 'git describe' to determine PROJECT_VER.
-- Building ESP-IDF components for target esp32p4
NOTICE: Dependencies lock doesn't exist, solving dependencies.
NOTICE: Using component placed at /Users/danielpaul/work/cm_testing/esp_usb_kconfig_repro/esp-usb-backend for dependency "esp-usb-backend", specified in /Users/danielpaul/work/cm_testing/esp_usb_kconfig_repro/app/main/idf_component.yml
NOTICE: Using component placed at /Users/danielpaul/work/cm_testing/esp_usb_kconfig_repro/esp-usb-wrp for dependency "esp-usb-wrp", specified in /Users/danielpaul/work/cm_testing/esp_usb_kconfig_repro/app/main/idf_component.yml
.NOTICE: Using component placed at /Users/danielpaul/work/cm_testing/esp_usb_kconfig_repro/esp-usb-backend for dependency "esp-usb-backend"(introduced by component "esp-usb-wrp"), specified in /Users/danielpaul/work/cm_testing/esp_usb_kconfig_repro/app/main/idf_component.yml
..NOTICE: Updating lock file at /Users/danielpaul/work/cm_testing/esp_usb_kconfig_repro/app/dependencies.lock
NOTICE: Processing 3 dependencies:
NOTICE: [1/3] esp-usb-backend (0.0.1) (/Users/danielpaul/work/cm_testing/esp_usb_kconfig_repro/esp-usb-backend)
NOTICE: [2/3] esp-usb-wrp (0.0.1) (/Users/danielpaul/work/cm_testing/esp_usb_kconfig_repro/esp-usb-wrp)
NOTICE: [3/3] idf (5.5.3)
CMake Warning at /Users/danielpaul/work/esp-idf/tools/cmake/build.cmake:629 (message):
  WARNING: The following Kconfig variables were used in "if" clauses, but not
  found in any Kconfig file:

      ESP_USB_BACKEND_CHERRYUSB, introduced by cherry-embedded/cherryusb, defined in /Users/danielpaul/work/cm_testing/esp_usb_kconfig_repro/esp-usb-backend/idf_component.yml
      ESP_USB_BACKEND_TINYUSB, introduced by roma-jam/tinyusb, defined in /Users/danielpaul/work/cm_testing/esp_usb_kconfig_repro/esp-usb-backend/idf_component.yml

  

Call Stack (most recent call first):
  /Users/danielpaul/work/esp-idf/tools/cmake/project.cmake:752 (idf_build_process)
  CMakeLists.txt:3 (project)


-- ESP-TEE is currently supported only on the esp32c6;esp32h2;esp32c5 SoCs
-- Project sdkconfig file /Users/danielpaul/work/cm_testing/esp_usb_kconfig_repro/app/sdkconfig
CMake Warning at /Users/danielpaul/work/esp-idf/tools/cmake/project.cmake:765 (message):
  Missing kconfig option.  Re-run the build process...
Call Stack (most recent call first):
  CMakeLists.txt:3 (project)


NOTICE: Skipping optional dependency: roma-jam/tinyusb
NOTICE: Optional dependency "cherry-embedded/cherryusb" of "esp-usb-backend (0.0.1) (/Users/danielpaul/work/cm_testing/esp_usb_kconfig_repro/esp-usb-backend)" is not present in the lock file, solving dependencies.
NOTICE: Using component placed at /Users/danielpaul/work/cm_testing/esp_usb_kconfig_repro/esp-usb-backend for dependency "esp-usb-backend", specified in /Users/danielpaul/work/cm_testing/esp_usb_kconfig_repro/app/main/idf_component.yml
NOTICE: Using component placed at /Users/danielpaul/work/cm_testing/esp_usb_kconfig_repro/esp-usb-wrp for dependency "esp-usb-wrp", specified in /Users/danielpaul/work/cm_testing/esp_usb_kconfig_repro/app/main/idf_component.yml
...NOTICE: Using component placed at /Users/danielpaul/work/cm_testing/esp_usb_kconfig_repro/esp-usb-backend for dependency "esp-usb-backend"(introduced by component "esp-usb-wrp"), specified in /Users/danielpaul/work/cm_testing/esp_usb_kconfig_repro/app/main/idf_component.yml
..NOTICE: Updating lock file at /Users/danielpaul/work/cm_testing/esp_usb_kconfig_repro/app/dependencies.lock
NOTICE: Processing 4 dependencies:
NOTICE: [1/4] cherry-embedded/cherryusb (1.5.2~2)
NOTICE: [2/4] esp-usb-backend (0.0.1) (/Users/danielpaul/work/cm_testing/esp_usb_kconfig_repro/esp-usb-backend)
NOTICE: [3/4] esp-usb-wrp (0.0.1) (/Users/danielpaul/work/cm_testing/esp_usb_kconfig_repro/esp-usb-wrp)
NOTICE: [4/4] idf (5.5.3)
-- enable cherryusb in esp-idf
-- ESP-TEE is currently supported only on the esp32c6;esp32h2;esp32c5 SoCs
NOTICE: Skipping optional dependency: roma-jam/tinyusb
-- Project sdkconfig file /Users/danielpaul/work/cm_testing/esp_usb_kconfig_repro/app/sdkconfig
-- Adding linker script /Users/danielpaul/work/esp-idf/components/riscv/ld/rom.api.ld
-- Found Python3: /Users/danielpaul/.espressif/python_env/idf5.5_py3.13_env/bin/python (found version "3.13.3") found components: Interpreter
-- Performing Test CMAKE_HAVE_LIBC_PTHREAD
-- Performing Test CMAKE_HAVE_LIBC_PTHREAD - Success
-- Found Threads: TRUE
-- Performing Test C_COMPILER_SUPPORTS_WFORMAT_SIGNEDNESS
-- Performing Test C_COMPILER_SUPPORTS_WFORMAT_SIGNEDNESS - Success
-- USING O3
-- App "esp_usb_kconfig_repro" version: 1
-- Adding linker script /Users/danielpaul/work/cm_testing/esp_usb_kconfig_repro/app/build/esp-idf/esp_system/ld/memory.ld
-- Adding linker script /Users/danielpaul/work/cm_testing/esp_usb_kconfig_repro/app/build/esp-idf/esp_system/ld/sections.ld.in
-- Adding linker script /Users/danielpaul/work/esp-idf/components/esp_rom/esp32p4/ld/esp32p4.rom.eco5.ld
-- Adding linker script /Users/danielpaul/work/esp-idf/components/esp_rom/esp32p4/ld/esp32p4.rom.api.ld
-- Adding linker script /Users/danielpaul/work/esp-idf/components/esp_rom/esp32p4/ld/esp32p4.rom.eco5.rvfp.ld
-- Adding linker script /Users/danielpaul/work/esp-idf/components/esp_rom/esp32p4/ld/esp32p4.rom.wdt.ld
-- Adding linker script /Users/danielpaul/work/esp-idf/components/esp_rom/esp32p4/ld/esp32p4.rom.systimer.ld
-- Adding linker script /Users/danielpaul/work/esp-idf/components/esp_rom/esp32p4/ld/esp32p4.rom.version.ld
-- Adding linker script /Users/danielpaul/work/esp-idf/components/esp_rom/esp32p4/ld/esp32p4.rom.eco5.libc.ld
-- Adding linker script /Users/danielpaul/work/esp-idf/components/esp_rom/esp32p4/ld/esp32p4.rom.libc-suboptimal_for_misaligned_mem.ld
-- Adding linker script /Users/danielpaul/work/esp-idf/components/esp_rom/esp32p4/ld/esp32p4.rom.eco5.newlib.ld
-- Adding linker script /Users/danielpaul/work/esp-idf/components/soc/esp32p4/ld/esp32p4.peripherals.ld
-- enable cherryusb in esp-idf
-- Components: app_trace app_update bootloader bootloader_support bt cherry-embedded__cherryusb cmock console cxx driver efuse esp-tls esp-usb-backend esp-usb-wrp esp_adc esp_app_format esp_bootloader_format esp_coex esp_common esp_driver_ana_cmpr esp_driver_bitscrambler esp_driver_cam esp_driver_dac esp_driver_gpio esp_driver_gptimer esp_driver_i2c esp_driver_i2s esp_driver_isp esp_driver_jpeg esp_driver_ledc esp_driver_mcpwm esp_driver_parlio esp_driver_pcnt esp_driver_ppa esp_driver_rmt esp_driver_sdio esp_driver_sdm esp_driver_sdmmc esp_driver_sdspi esp_driver_spi esp_driver_touch_sens esp_driver_tsens esp_driver_twai esp_driver_uart esp_driver_usb_serial_jtag esp_eth esp_event esp_gdbstub esp_hal_ieee802154 esp_hid esp_http_client esp_http_server esp_https_ota esp_https_server esp_hw_support esp_lcd esp_local_ctrl esp_mm esp_netif esp_netif_stack esp_partition esp_phy esp_pm esp_psram esp_ringbuf esp_rom esp_security esp_system esp_timer esp_vfs_console esp_wifi espcoredump esptool_py fatfs freertos hal heap http_parser idf_test ieee802154 json log lwip main mbedtls mqtt newlib nvs_flash nvs_sec_provider openthread partition_table protobuf-c protocomm pthread riscv rt sdmmc soc spi_flash spiffs tcp_transport ulp unity usb vfs wear_levelling wifi_provisioning wpa_supplicant
-- Component paths: /Users/danielpaul/work/esp-idf/components/app_trace /Users/danielpaul/work/esp-idf/components/app_update /Users/danielpaul/work/esp-idf/components/bootloader /Users/danielpaul/work/esp-idf/components/bootloader_support /Users/danielpaul/work/esp-idf/components/bt /Users/danielpaul/work/cm_testing/esp_usb_kconfig_repro/app/managed_components/cherry-embedded__cherryusb /Users/danielpaul/work/esp-idf/components/cmock /Users/danielpaul/work/esp-idf/components/console /Users/danielpaul/work/esp-idf/components/cxx /Users/danielpaul/work/esp-idf/components/driver /Users/danielpaul/work/esp-idf/components/efuse /Users/danielpaul/work/esp-idf/components/esp-tls /Users/danielpaul/work/cm_testing/esp_usb_kconfig_repro/esp-usb-backend /Users/danielpaul/work/cm_testing/esp_usb_kconfig_repro/esp-usb-wrp /Users/danielpaul/work/esp-idf/components/esp_adc /Users/danielpaul/work/esp-idf/components/esp_app_format /Users/danielpaul/work/esp-idf/components/esp_bootloader_format /Users/danielpaul/work/esp-idf/components/esp_coex /Users/danielpaul/work/esp-idf/components/esp_common /Users/danielpaul/work/esp-idf/components/esp_driver_ana_cmpr /Users/danielpaul/work/esp-idf/components/esp_driver_bitscrambler /Users/danielpaul/work/esp-idf/components/esp_driver_cam /Users/danielpaul/work/esp-idf/components/esp_driver_dac /Users/danielpaul/work/esp-idf/components/esp_driver_gpio /Users/danielpaul/work/esp-idf/components/esp_driver_gptimer /Users/danielpaul/work/esp-idf/components/esp_driver_i2c /Users/danielpaul/work/esp-idf/components/esp_driver_i2s /Users/danielpaul/work/esp-idf/components/esp_driver_isp /Users/danielpaul/work/esp-idf/components/esp_driver_jpeg /Users/danielpaul/work/esp-idf/components/esp_driver_ledc /Users/danielpaul/work/esp-idf/components/esp_driver_mcpwm /Users/danielpaul/work/esp-idf/components/esp_driver_parlio /Users/danielpaul/work/esp-idf/components/esp_driver_pcnt /Users/danielpaul/work/esp-idf/components/esp_driver_ppa /Users/danielpaul/work/esp-idf/components/esp_driver_rmt /Users/danielpaul/work/esp-idf/components/esp_driver_sdio /Users/danielpaul/work/esp-idf/components/esp_driver_sdm /Users/danielpaul/work/esp-idf/components/esp_driver_sdmmc /Users/danielpaul/work/esp-idf/components/esp_driver_sdspi /Users/danielpaul/work/esp-idf/components/esp_driver_spi /Users/danielpaul/work/esp-idf/components/esp_driver_touch_sens /Users/danielpaul/work/esp-idf/components/esp_driver_tsens /Users/danielpaul/work/esp-idf/components/esp_driver_twai /Users/danielpaul/work/esp-idf/components/esp_driver_uart /Users/danielpaul/work/esp-idf/components/esp_driver_usb_serial_jtag /Users/danielpaul/work/esp-idf/components/esp_eth /Users/danielpaul/work/esp-idf/components/esp_event /Users/danielpaul/work/esp-idf/components/esp_gdbstub /Users/danielpaul/work/esp-idf/components/esp_hal_ieee802154 /Users/danielpaul/work/esp-idf/components/esp_hid /Users/danielpaul/work/esp-idf/components/esp_http_client /Users/danielpaul/work/esp-idf/components/esp_http_server /Users/danielpaul/work/esp-idf/components/esp_https_ota /Users/danielpaul/work/esp-idf/components/esp_https_server /Users/danielpaul/work/esp-idf/components/esp_hw_support /Users/danielpaul/work/esp-idf/components/esp_lcd /Users/danielpaul/work/esp-idf/components/esp_local_ctrl /Users/danielpaul/work/esp-idf/components/esp_mm /Users/danielpaul/work/esp-idf/components/esp_netif /Users/danielpaul/work/esp-idf/components/esp_netif_stack /Users/danielpaul/work/esp-idf/components/esp_partition /Users/danielpaul/work/esp-idf/components/esp_phy /Users/danielpaul/work/esp-idf/components/esp_pm /Users/danielpaul/work/esp-idf/components/esp_psram /Users/danielpaul/work/esp-idf/components/esp_ringbuf /Users/danielpaul/work/esp-idf/components/esp_rom /Users/danielpaul/work/esp-idf/components/esp_security /Users/danielpaul/work/esp-idf/components/esp_system /Users/danielpaul/work/esp-idf/components/esp_timer /Users/danielpaul/work/esp-idf/components/esp_vfs_console /Users/danielpaul/work/esp-idf/components/esp_wifi /Users/danielpaul/work/esp-idf/components/espcoredump /Users/danielpaul/work/esp-idf/components/esptool_py /Users/danielpaul/work/esp-idf/components/fatfs /Users/danielpaul/work/esp-idf/components/freertos /Users/danielpaul/work/esp-idf/components/hal /Users/danielpaul/work/esp-idf/components/heap /Users/danielpaul/work/esp-idf/components/http_parser /Users/danielpaul/work/esp-idf/components/idf_test /Users/danielpaul/work/esp-idf/components/ieee802154 /Users/danielpaul/work/esp-idf/components/json /Users/danielpaul/work/esp-idf/components/log /Users/danielpaul/work/esp-idf/components/lwip /Users/danielpaul/work/cm_testing/esp_usb_kconfig_repro/app/main /Users/danielpaul/work/esp-idf/components/mbedtls /Users/danielpaul/work/esp-idf/components/mqtt /Users/danielpaul/work/esp-idf/components/newlib /Users/danielpaul/work/esp-idf/components/nvs_flash /Users/danielpaul/work/esp-idf/components/nvs_sec_provider /Users/danielpaul/work/esp-idf/components/openthread /Users/danielpaul/work/esp-idf/components/partition_table /Users/danielpaul/work/esp-idf/components/protobuf-c /Users/danielpaul/work/esp-idf/components/protocomm /Users/danielpaul/work/esp-idf/components/pthread /Users/danielpaul/work/esp-idf/components/riscv /Users/danielpaul/work/esp-idf/components/rt /Users/danielpaul/work/esp-idf/components/sdmmc /Users/danielpaul/work/esp-idf/components/soc /Users/danielpaul/work/esp-idf/components/spi_flash /Users/danielpaul/work/esp-idf/components/spiffs /Users/danielpaul/work/esp-idf/components/tcp_transport /Users/danielpaul/work/esp-idf/components/ulp /Users/danielpaul/work/esp-idf/components/unity /Users/danielpaul/work/esp-idf/components/usb /Users/danielpaul/work/esp-idf/components/vfs /Users/danielpaul/work/esp-idf/components/wear_levelling /Users/danielpaul/work/esp-idf/components/wifi_provisioning /Users/danielpaul/work/esp-idf/components/wpa_supplicant
-- Configuring done (6.9s)
-- Generating done (0.7s)
-- Build files have been written to: /Users/danielpaul/work/cm_testing/esp_usb_kconfig_repro/app/build

[roma-jam]

Hi @XDanielPaul,

thanks for the efforts! This is exactly what do I have in my setup. Thanks for reproducing it locally.

The question from my original topic was:

I am not able to get rid of the message during the config:

WARNING: The following Kconfig variables were used in "if" clauses, but not
found in any Kconfig file:

  ESP_USB_BACKEND_CHERRYUSB, introduced by cherry-embedded/cherryusb, defined in /Users/danielpaul/work/cm_testing/esp_usb_kconfig_repro/esp-usb-backend/idf_component.yml
  ESP_USB_BACKEND_TINYUSB, introduced by roma-jam/tinyusb, defined in /Users/danielpaul/work/cm_testing/esp_usb_kconfig_repro/esp-usb-backend/idf_component.yml

And you also has the same in your log.

Why this is important for me?

Because I want to use idf-apps-build find and then idf-apps-build build and this warning is treated as an error:

[02/27/26 19:16:55] WARNING    WARNING: The following Kconfig variables were used in "if" clauses, but not
[02/27/26 19:16:55] ERROR    Build failed and keep_going=False, stopping build process

So, two more questions:

1. Am I able to use idf-build-apps in such project (with --keep-going argument)?
2. Am I able to use the Kconfig parameters from esp-usb-wrp (CONFIG_ESP_USB_BACKEND_CHERRYUSB and CONFIG_ESP_USB_BACKEND_TINYUSB) in CMakeLists.txt in esp-usb-backend/CMakeLists.txt?

Thanks in advance and wish you a great weekend!

UPD:

Also doesn't this approach seem to be too difficult? Is there any other way I can achieve the same (component backend selection) but easier?

[XDanielPaul]

Hi @roma-jam,

I understand why it's important for you and we are already aware of this warning issue being treated as error.

Good news are, that it has already been solved and is going to be available in an upcoming IDF Component Manager release. We are planning to emit this warning only if the symbol truly doesn’t exist after the entire configuration phase (Not prematurely during intermediate runs).

The change is already available in the main branch (development version) of the IDF Component Manager, so if you install it in your workflow

https://github.com/espressif/idf-component-manager?tab=readme-ov-file#installing-a-development-version-of-the-component-manager

it will eliminate the warning until the official release lands (sorry, this approach might be inconvenient - we are planning to make the new release with fix included happen soon!)

As for your questions

1. idf-build-apps developers might give you a better answer, but from my rough knowledge --keep-going should work, or you could use either --ignore-warning-strs/--ignore-warning-file/--ignore-warning-files
2. You can use KConfig parameters from esp-usb-wrp in the esp-usb-backend/CMakeLists.txt i.e.

esp-usb-backend/CMakeLists.txt

idf_component_register(SRCS "backend.c")

if(CONFIG_ESP_USB_BACKEND_CHERRYUSB)
    message(STATUS "Using CherryUSB backend")
endif()

As for the difficulty of approach - I cannot really give you an experienced opinion as I am not an active component developer - there could be a better approach to your particular use case, but I cannot think of one at the moment

[roma-jam]

Thanks @XDanielPaul, no more questions for now.

Thanks for the confirmation!

[XDanielPaul]

@roma-jam Excellent, I'm glad I could help you! 🚀

If you have any other problems feel free to open an issue :)

[XDanielPaul]

Should be fixed now with v2.4.7