clang make work for samd21

examples/build_system/make/toolchain/arm_clang.mk

@@ -0,0 +1,10 @@
+CC = clang
+CXX = clang++
+AS = $(CC) -x assembler-with-cpp
+LD = $(CC)
+
+GDB = $(CROSS_COMPILE)gdb
+OBJCOPY = llvm-objcopy
+SIZE = llvm-size
+
+include ${TOP}/examples/build_system/make/toolchain/gcc_common.mk

examples/build_system/make/toolchain/arm_gcc.mk

@@ -12,73 +12,9 @@ GDB = $(CROSS_COMPILE)gdb
 OBJCOPY = $(CROSS_COMPILE)objcopy
 SIZE = $(CROSS_COMPILE)size
 
-CC_VERSION := $(shell $(CC) -dumpversion)
-CC_VERSION_MAJOR = $(firstword $(subst ., ,$(CC_VERSION)))
-
-# ---------------------------------------
-# Compiler Flags
-# ---------------------------------------
 CFLAGS += \
-  -MD \
-  -ggdb \
-  -fdata-sections \
-  -ffunction-sections \
   -fsingle-precision-constant \
-  -fno-strict-aliasing \
-  -Wall \
-  -Wextra \
-  -Werror \
-  -Wfatal-errors \
-  -Wdouble-promotion \
-  -Wstrict-prototypes \
-  -Wstrict-overflow \
-  -Werror-implicit-function-declaration \
-  -Wfloat-equal \
-  -Wundef \
-  -Wshadow \
-  -Wwrite-strings \
-  -Wsign-compare \
-  -Wmissing-format-attribute \
-  -Wunreachable-code \
-  -Wcast-align \
-  -Wcast-function-type \
-  -Wcast-qual \
-  -Wnull-dereference \
-  -Wuninitialized \
-  -Wunused \
-  -Wreturn-type \
-  -Wredundant-decls \
 
-# conversion is too strict for most mcu driver, may be disable sign/int/arith-conversion
-#  -Wconversion
+LIBS += -lgcc -lm -lnosys
 
-# Size Optimization as default
-CFLAGS_OPTIMIZED ?= -Os
-
-# Debugging/Optimization
-ifeq ($(DEBUG), 1)
-  CFLAGS += -O0
-  NO_LTO = 1
-else
-  CFLAGS += $(CFLAGS_OPTIMIZED)
-endif
-
-# ---------------------------------------
-# Linker Flags
-# ---------------------------------------
-LDFLAGS += \
-  -Wl,-Map=$@.map \
-  -Wl,-cref \
-  -Wl,-gc-sections \
-
-# renesas rx does not support --print-memory-usage flags
-ifneq ($(FAMILY),rx)
-LDFLAGS += -Wl,--print-memory-usage
-endif
-
-# from version 12
-ifeq ($(strip $(if $(CMDEXE),\
-               $(shell if $(CC_VERSION_MAJOR) geq 12 (echo 1) else (echo 0)),\
-               $(shell expr $(CC_VERSION_MAJOR) \>= 12))), 1)
-LDFLAGS += -Wl,--no-warn-rwx-segment
-endif
+include ${TOP}/examples/build_system/make/toolchain/gcc_common.mk

examples/build_system/make/toolchain/clang_rules.mk

@@ -0,0 +1 @@
+include ${TOP}/examples/build_system/make/toolchain/gcc_rules.mk

examples/build_system/make/toolchain/gcc_common.mk

@@ -0,0 +1,71 @@
+# ---------------------------------------
+# Compiler Flags
+# ---------------------------------------
+CFLAGS += \
+  -MD \
+  -ggdb \
+  -fdata-sections \
+  -ffunction-sections \
+  -fno-strict-aliasing \
+  -Wall \
+  -Wextra \
+  -Werror \
+  -Wfatal-errors \
+  -Wdouble-promotion \
+  -Wstrict-prototypes \
+  -Wstrict-overflow \
+  -Werror-implicit-function-declaration \
+  -Wfloat-equal \
+  -Wundef \
+  -Wshadow \
+  -Wwrite-strings \
+  -Wsign-compare \
+  -Wmissing-format-attribute \
+  -Wunreachable-code \
+  -Wcast-align \
+  -Wcast-function-type \
+  -Wcast-qual \
+  -Wnull-dereference \
+  -Wuninitialized \
+  -Wunused \
+  -Wreturn-type \
+  -Wredundant-decls \
+
+# conversion is too strict for most mcu driver, may be disable sign/int/arith-conversion
+#  -Wconversion
+
+# Size Optimization as default
+CFLAGS_OPTIMIZED ?= -Os
+
+# Debugging/Optimization
+ifeq ($(DEBUG), 1)
+  CFLAGS += -O0
+  NO_LTO = 1
+else
+  CFLAGS += $(CFLAGS_OPTIMIZED)
+endif
+
+# ---------------------------------------
+# Linker Flags
+# ---------------------------------------
+LDFLAGS += \
+  -Wl,-Map=$@.map \
+  -Wl,--cref \
+  -Wl,-gc-sections \
+
+# renesas rx does not support --print-memory-usage flags
+ifneq ($(FAMILY),rx)
+LDFLAGS += -Wl,--print-memory-usage
+endif
+
+ifeq ($(TOOLCHAIN),gcc)
+CC_VERSION := $(shell $(CC) -dumpversion)
+CC_VERSION_MAJOR = $(firstword $(subst ., ,$(CC_VERSION)))
+
+# from version 12
+ifeq ($(strip $(if $(CMDEXE),\
+               $(shell if $(CC_VERSION_MAJOR) geq 12 (echo 1) else (echo 0)),\
+               $(shell expr $(CC_VERSION_MAJOR) \>= 12))), 1)
+LDFLAGS += -Wl,--no-warn-rwx-segment
+endif
+endif

examples/build_system/make/toolchain/gcc_rules.mk

@@ -21,8 +21,13 @@ ifneq ($(CFLAGS_SKIP),)
 CFLAGS := $(filter-out $(CFLAGS_SKIP),$(CFLAGS))
 endif
 
+ifeq ($(TOOLCHAIN),clang)
+LDFLAGS += $(CFLAGS) $(LDFLAGS_CLANG)
+else
 LDFLAGS += $(CFLAGS) $(LDFLAGS_GCC)
+endif
 
+# TODO should be removed after all examples are updated
 ifdef LD_FILE
 LDFLAGS += -Wl,-T,$(TOP)/$(LD_FILE)
 endif
@@ -33,11 +38,7 @@ endif
 
 ASFLAGS += $(CFLAGS)
 
-LIBS_GCC ?= -lgcc -lm -lnosys
-
 # libc
-LIBS += $(LIBS_GCC)
-
 ifneq ($(BOARD), spresense)
 LIBS += -lc
 endif