Fix lto

[pennam]

@facchinm i had to slightly change the custom.json file rto reach the same level of ROM optimization of lto.json otherwise the binary won't fit for portenta.

see 5c1c578

Could you give it a spin with your toolchain to check if it still works for you?

[facchinm]

I get [ERROR] Attempt to override undefined parameter 'mcuboot.encrypt-scratch' in 'application[PORTENTA_H7_M7]' , maybe mbed-os.lib is outdated?

[pennam]

I get [ERROR] Attempt to override undefined parameter 'mcuboot.encrypt-scratch' in 'application[PORTENTA_H7_M7]' , maybe mbed-os.lib is outdated?

🤔 it looks correct...

From a new folder this works for me:

git clone https://github.com/arduino/mcuboot-arduino-stm32h7.git
cd mcuboot-arduino-stm32h7/
mbed config root . && mbed deploy
git fetch origin
git checkout origin/fix-lto
mbed compile -m PORTENTA_H7_M7 -t GCC_ARM --profile=release --profile custom.json