Adding experimental clang compiler support for arm-none-eabi

- Currently builds larger binaries than gcc (RAM)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 346602dddf14b1da9126a222145586f5fe347a83..b8962087b659db25f092fb865d0e7edbb2674e3f 100644 (file)
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -28,6 +28,20 @@ set( CHIP
 
 
 
+###
+# Compiler Selection
+#
+
+#| *** EXPERIMENTAL ***
+#| Stick with gcc unless you know what you're doing
+#| Currently only arm is supported with clang
+set( COMPILER
+       "gcc"   # arm-none-eabi-gcc / avr-gcc - Default
+#      "clang" # arm-none-eabi
+       CACHE STRING "Compiler Type" )
+
+
+
 ###
 # Compiler Intialization
 #

diff --git a/Lib/CMake/arm.cmake b/Lib/CMake/arm.cmake
index 52973d4835c609520668a60a5a3c297c74c5dffb..b468ae28e431f3cb34cec43a0c25b52b0dbbead7 100644 (file)
--- a/Lib/CMake/arm.cmake
+++ b/Lib/CMake/arm.cmake
@@ -13,9 +13,20 @@
 
 #| Set the Compilers (must be set first)
 include( CMakeForceCompiler )
-cmake_force_c_compiler  ( arm-none-eabi-gcc ARMCCompiler )
-cmake_force_cxx_compiler( arm-none-eabi-g++ ARMCxxCompiler )
-set( _CMAKE_TOOLCHAIN_PREFIX arm-none-eabi- )
+message( STATUS "Compiler Selected:" )
+if ( "${COMPILER}" MATCHES "gcc" )
+       cmake_force_c_compiler  ( arm-none-eabi-gcc ARMCCompiler )
+       cmake_force_cxx_compiler( arm-none-eabi-g++ ARMCxxCompiler )
+       set( _CMAKE_TOOLCHAIN_PREFIX arm-none-eabi- )
+       message( "gcc" )
+elseif ( "${COMPILER}" MATCHES "clang" )
+       cmake_force_c_compiler  ( clang   ARMCCompiler )
+       cmake_force_cxx_compiler( clang++ ARMCxxCompiler )
+       set( _CMAKE_TOOLCHAIN_PREFIX llvm- )
+       message( "clang" )
+else ()
+       message( AUTHOR_WARNING "COMPILER: ${COMPILER} - Unknown compiler selection" )
+endif ()
 
 
 
@@ -134,6 +145,8 @@ set( WARN "-Wall -ggdb3" )
 if( BOOTLOADER )
        set( TUNING "-D_bootloader_ -Wno-main -msoft-float -mthumb -fplan9-extensions -ffunction-sections -fdata-sections -fno-builtin -fstrict-volatile-bitfields -flto -fno-use-linker-plugin -nostdlib" )
        #set( TUNING "-mthumb -fdata-sections -ffunction-sections -fno-builtin -msoft-float -fstrict-volatile-bitfields -flto -fno-use-linker-plugin -fwhole-program -Wno-main -nostartfiles -fplan9-extensions -D_bootloader_" )
+elseif ( "${COMPILER}" MATCHES "clang" )
+       set( TUNING "-target arm-none-eabi -mthumb -nostdlib -fdata-sections -ffunction-sections -fshort-wchar -fno-builtin" )
 else()
        set( TUNING "-mthumb -nostdlib -fdata-sections -ffunction-sections -fshort-wchar -fno-builtin -nostartfiles" )
 endif()
@@ -181,5 +194,9 @@ set( BIN_FLAGS -O binary )
 
 
 #| Lss Flags
-set( LSS_FLAGS -h -S -z )
+if ( "${COMPILER}" MATCHES "clang" )
+       set( LSS_FLAGS -section-headers -triple=arm-none-eabi )
+else ()
+       set( LSS_FLAGS -h -S -z )
+endif ()
 

diff --git a/Lib/CMake/build.cmake b/Lib/CMake/build.cmake
index ece5ee209fe7e074d1a95daf9b17cca7965d4ba6..676e55766951de56ef1c2f1dac3a7b4011012f2d 100644 (file)
--- a/Lib/CMake/build.cmake
+++ b/Lib/CMake/build.cmake
@@ -33,22 +33,33 @@ set_target_properties( ${TARGET_ELF} PROPERTIES
        SUFFIX ""                               # XXX Force Windows to keep the .exe off
 )
 
+#| llvm-clang does not have an objcopy equivalent
+if ( "${COMPILER}" MATCHES "clang" )
+       if ( "${COMPILER_FAMILY}" MATCHES "arm" )
+               set ( OBJ_COPY arm-none-eabi-objcopy )
+       elseif ( "${COMPILER_FAMILY}" MATCHES "arm" )
+               set ( OBJ_COPY avr-objcopy )
+       endif ()
+else ()
+       set ( OBJ_COPY ${CMAKE_OBJCOPY} )
+endif ()
+
 
 #| Convert the .ELF into a .bin to load onto the McHCK
-if( DEFINED DFU )
+if ( DEFINED DFU )
        set( TARGET_BIN ${TARGET}.dfu.bin )
        add_custom_command( TARGET ${TARGET_ELF} POST_BUILD
-               COMMAND ${CMAKE_OBJCOPY} ${BIN_FLAGS} ${TARGET_ELF} ${TARGET_BIN}
+               COMMAND ${OBJ_COPY} ${BIN_FLAGS} ${TARGET_ELF} ${TARGET_BIN}
                COMMENT "Creating dfu binary file:      ${TARGET_BIN}"
        )
-endif()
+endif ()
 
 
 #| Convert the .ELF into a .HEX to load onto the Teensy
 if ( DEFINED TEENSY )
        set( TARGET_HEX ${TARGET}.teensy.hex )
        add_custom_command( TARGET ${TARGET_ELF} POST_BUILD
-               COMMAND ${CMAKE_OBJCOPY} ${HEX_FLAGS} ${TARGET_ELF} ${TARGET_HEX}
+               COMMAND ${OBJ_COPY} ${HEX_FLAGS} ${TARGET_ELF} ${TARGET_HEX}
                COMMENT "Creating iHex file to load:    ${TARGET_HEX}"
        )
 endif()