Makefile: don't pass -mstrict-align if not supported

Support for that option will be added in LLVM 18:
23ce536840

Clang 17.0.6, however, will error when passed the
`-mstrict-align` flag.
We should only use the flag if it is supported.

Signed-off-by: Kalle Wachsmuth <kalle.wachsmuth@gmail.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Reviewed-by: Xiang W <wxjstz@126.com>
This commit is contained in:
Kalle Wachsmuth 2024-01-18 19:02:31 +01:00 committed by Anup Patel
parent 21caaa3f56
commit 4a76f79ff5

View file

@ -170,6 +170,9 @@ OPENSBI_LD_PIE := $(shell $(CC) $(CLANG_TARGET) $(RELAX_FLAG) $(USE_LD_FLAG) -fP
# Check whether the compiler supports -m(no-)save-restore
CC_SUPPORT_SAVE_RESTORE := $(shell $(CC) $(CLANG_TARGET) $(RELAX_FLAG) -nostdlib -mno-save-restore -x c /dev/null -o /dev/null 2>&1 | grep -e "-save-restore" >/dev/null && echo n || echo y)
# Check whether the compiler supports -m(no-)strict-align
CC_SUPPORT_STRICT_ALIGN := $(shell $(CC) $(CLANG_TARGET) $(RELAX_FLAG) -nostdlib -mstrict-align -x c /dev/null -o /dev/null 2>&1 | grep -e "-mstrict-align\|-mno-unaligned-access" >/dev/null && echo n || echo y)
# Check whether the assembler and the compiler support the Zicsr and Zifencei extensions
CC_SUPPORT_ZICSR_ZIFENCEI := $(shell $(CC) $(CLANG_TARGET) $(RELAX_FLAG) -nostdlib -march=rv$(OPENSBI_CC_XLEN)imafd_zicsr_zifencei -x c /dev/null -o /dev/null 2>&1 | grep "zicsr\|zifencei" > /dev/null && echo n || echo y)
@ -337,11 +340,14 @@ CFLAGS += -O0
else
CFLAGS += -O2
endif
CFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls -mstrict-align
# enable -m(no-)save-restore option by CC_SUPPORT_SAVE_RESTORE
CFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls
# Optionally supported flags
ifeq ($(CC_SUPPORT_SAVE_RESTORE),y)
CFLAGS += -mno-save-restore
endif
ifeq ($(CC_SUPPORT_STRICT_ALIGN),y)
CFLAGS += -mstrict-align
endif
CFLAGS += -mabi=$(PLATFORM_RISCV_ABI) -march=$(PLATFORM_RISCV_ISA)
CFLAGS += -mcmodel=$(PLATFORM_RISCV_CODE_MODEL)
CFLAGS += $(RELAX_FLAG)
@ -355,11 +361,14 @@ CPPFLAGS += $(platform-cppflags-y)
CPPFLAGS += $(firmware-cppflags-y)
ASFLAGS = -g -Wall -nostdlib
ASFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls -mstrict-align
# enable -m(no-)save-restore option by CC_SUPPORT_SAVE_RESTORE
ASFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls
# Optionally supported flags
ifeq ($(CC_SUPPORT_SAVE_RESTORE),y)
ASFLAGS += -mno-save-restore
endif
ifeq ($(CC_SUPPORT_STRICT_ALIGN),y)
ASFLAGS += -mstrict-align
endif
ASFLAGS += -mabi=$(PLATFORM_RISCV_ABI) -march=$(PLATFORM_RISCV_ISA)
ASFLAGS += -mcmodel=$(PLATFORM_RISCV_CODE_MODEL)
ASFLAGS += $(RELAX_FLAG)