I am using VSCode and ESP-IDF to program Arduino. Some of the Arduino library files are generating warnings such as below.
988/1135] Building CXX object esp-idf/arduino/CMakeFiles/__idf_arduino.dir/libraries/WiFi/src/WiFiScan.cpp.obj
/Users/sr/projects/gcp-iot/components/arduino/libraries/WiFi/src/WiFiScan.cpp:45:21: warning: 'const char* cipher_str(int)' defined but not used [-Wunused-function]
static const char * cipher_str(int cipher)
^~~~~~~~~~
[1003/1135] Building CXX object esp-idf/arduino/CMakeFiles/__idf_arduino.dir/libraries/WiFi/src/WiFiGeneric.cpp.obj
/Users/sr/projects/gcp-iot/components/arduino/libraries/WiFi/src/WiFiGeneric.cpp:187:21: warning: 'const char* auth_mode_str(int)' defined but not used [-Wunused-function]
static const char * auth_mode_str(int authmode)
^~~~~~~~~~~~~
[1013/1135] Building CXX object esp-idf/arduino/CMakeFiles/__idf_arduino.dir/libraries/Wire/src/Wire.cpp.obj
/Users/sr/projects/gcp-iot/components/arduino/libraries/Wire/src/Wire.cpp: In member function 'uint8_t TwoWire::requestFrom(uint16_t, uint8_t, bool)':
/Users/sriraj/projects/gcp-iot/components/arduino/libraries/Wire/src/Wire.cpp:363:15: warning: variable 'err' set but not used [-Wunused-but-set-variable]
esp_err_t err = ESP_OK;
I have tried setting -Wno-unused-function flag in various places but have failed to disable these warnings. Can someone please advise the right place to set this build option so I don't see these warnings. I am using VSCode on MacOS. Thank you in advance.
Navigate to your ESP-IDF directory and look for build.cmake file under esp-idf/tools/cmake directory.
In the build.cmake file - look for the section called function(__build_set_default_build_specifications) - this contains all the default compiler options that are executed at build time. Include -Wno-unused-function here, save and recompile your project!
But be aware that this will disable this warning globally and affect other projects as well.