Cross Compiling With arm-none-eabi-gvcc

Hello, I'm trying to cross compile with arm-none-eabi-gcc on an Ubuntu x64 build machine.

My CMake toolchain file contains the following flags:

mcpu=cortex-m4 -mthumb -mfloat-abi=soft -fdata-sections -ffunction-sections \ --specs=rdimon.specs -lgcc -lc -lm -lrdimon

I invoke CMake with:

cmake -DCMAKE_TOOLCHAIN_FILE=arm-none-eabi-gcc-mcu.cmake \ -DCMAKE_INSTALL_PREFIX=$HOME/prog/cross/arm -DBUILD_STATIC_LIB=ON \ -DWITH_STATIC_LIB=ON -DWITH_EXAMPLES=OFF -Bbuild cmake --build build/

I get implicit declaration errors relating to clock_gettime(), sigsetjmp(), siglongjmp() and other signal functions. These are linux specific functions and so are obviously not present on a bare-metal machine.

How do I resolve these errors? Thanks

-- Ryan McClue, Sydney