We use armclang with `-masm=auto` to auto-select which assembler to use
based on the syntax of the file. Cortex-M55 isn't supported by armasm,
but we don't yet have GCC-syntax asm files for ARM compiler
(1dd090bd1c/CMSIS/RTOS2/RTX/Source/ARM/irq_armv8mml.s).
$ armclang --target=arm-arm-none-eabi -mcpu=cortex-m55 -mfpu=none -masm=auto -c cmsis/CMSIS_5/CMSIS/RTOS2/RTX/Source/TOOLCHAIN_ARM/TARGET_M33/irq_armv8mml.S
armclang: error: armasm does not support CPU 'cortex-m55'
In the mean time, we can build C and C++ files using the
`-mcpu=cortex-m55` option, and for armasm, cancel out that choice of CPU
with a known-supported CPU type, Cortex-R7, and provide the legacy
assembler-specific option `-Wa,armasm,--cpu=cortex-m55`.
After these changes, this works:
$ armclang --target=arm-arm-none-eabi -mcpu=cortex-m55 -mcpu=cortex-r7 -Wa,--cpu=cortex-m55 -mfpu=none -masm=auto -c cmsis/CMSIS_5/CMSIS/RTOS2/RTX/Source/TOOLCHAIN_ARM/TARGET_M33/irq_armv8mml.S
Meano
Werner Lewis
Jaeden Amero
Martin Kojtal