OSX ESP firmware build notes

error: unknown type name 'ptrdiff_t' when installing pass-2 core C compiler.

Solution: https://github.com/pfalcon/esp-open-sdk/issues/45 delete define/endef statements

Relevant output

Xtensa toolchain is built, to use it:

export PATH=/Users/aria/code/espbuild/esp-open-sdk/xtensa-lx106-elf/bin:$PATH

Espressif ESP8266 SDK is installed. Toolchain contains only Open Source components To link external proprietary libraries add:

xtensa-lx106-elf-gcc -I/Users/aria/code/espbuild/esp-open-sdk/sdk/include -L/Users/aria/code/espbuild/esp-open-sdk/sdk/lib