set(CMAKE_SYSTEM_NAME Generic) set(CMAKE_C_COMPILER clang) set(CMAKE_CXX_COMPILER clang++) set(CMAKE_ASM_COMPILER clang) set(CMAKE_AR xtensa-esp32-elf-ar) set(CMAKE_RANLIB xtensa-esp32-elf-gcc-ranlib) set(CMAKE_OBJDUMP xtensa-esp32-elf-objdump) # -freestanding is a hack to force Clang to use its own stdatomic.h, # without falling back to the (incompatible) GCC stdatomic.h # https://github.com/espressif/llvm-project/blob/d9341b81/clang/lib/Headers/stdatomic.h#L13-L18 set(CMAKE_C_FLAGS "--target=xtensa -mcpu=esp32 -ffreestanding" CACHE STRING "C Compiler Base Flags") set(CMAKE_CXX_FLAGS "--target=xtensa -mcpu=esp32 -ffreestanding" CACHE STRING "C++ Compiler Base Flags") set(CMAKE_ASM_FLAGS "--target=xtensa -mcpu=esp32" CACHE STRING "Assembler Base Flags")