Allow compressed flash updates by earlephilhower · Pull Request #6820 · esp8266/Arduino (original) (raw)

As part of the compressed OTA image work, we will need to be able to
build the bootloader using -O2 to minimize code size for the
decompressor.

It was as -O0 which does no code optimization whatsoever because there
was a bit of quasi-assembly that was optimized out with any other
setting. Building uzlib with -O0 is probably a bad thing and will wind
up much larger than with -O2.

Rewrite the jump-to-app code in pure ASM to avoid the optimization
issue.

Add -Wall and clean up warnings it generates.

Remove call to esptool-ck and generation of unused eboot.bin application
image since it is not used by the Arduino core.