The definition in `pkg/esp32_sdk/Makefile.include` was evaluated by
`make` after the include paths were already set, resulting in
`ESP32_SDK_DIR` being empty in
INCLUDES += -I$(ESP32_SDK_DIR)/components
[...]
This in turn resulted in
cc1: error: /components: No such file or directory [-Werror=missing-include-dirs]
[...]
The patches include the following changes:
- define ARRAY_SIZE in `component/spi_flash/spi_flash_timing_tuning.c` only if it is not yet defined by RIOT macros
- add alternative implementations for`spi_flash_disable_interrupts_caches_and_other_cpu` and `spi_flash_enable_interrupts_caches_and_other_cpu` if compiled for RIOT
- fix the undefined reference to `rtc_gpio_force_hold_en_all` in `components/driver/gpio.c`
- rename the bootloader patch to fix the serial number
The shared `build-libs` directory needs to be available for
modules/packages that depend on the SDK before that package
is eventually compiled.
This also includes header files such as `esp32_idf_version.h`.
Packages are downloaded, patched, prepared before any module
is compiled. By adding the directory creation and header as
a dependency of `PKG_PREPARE` we make sure the rules are ran
before compilation starts.
The vendor binary libraries of ESP-IDF are provided as a separate GIT repository. These libraries are defined as separate package for two reasons: 1. RIOT packages don't support to clone GIT repositories recursively; 2. ESP-IDF pulls a lot of other GIT repositories that are not needed when it is cloned recursively.
