qemu-e2k/pc-bios/optionrom/Makefile
Christian Ehrhardt 9584d3d00a build: disable fcf-protection on -march=486 -m16
Some of the roms build with -march=i486 -m16 which is incompatible
with -fcf-protection. That in turn is can be set by default, for
example in Ubuntu [1].
That causes:
 cc1: error: ‘-fcf-protection’ is not compatible with this target

This won't work on -march=i486 -m16 and no matter if set or not we can
override it to "none" if the option is known to the compiler to be
able to build reliably.

Fixes: https://gitlab.com/qemu-project/qemu/-/issues/889

[1]: https://wiki.ubuntu.com/ToolChain/CompilerFlags#A-fcf-protection

Signed-off-by: Christian Ehrhardt <christian.ehrhardt@canonical.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20220323090713.1002588-1-christian.ehrhardt@canonical.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-03-24 18:44:07 +01:00

74 lines
2.4 KiB
Makefile

include config.mak
SRC_DIR := $(TOPSRC_DIR)/pc-bios/optionrom
VPATH = $(SRC_DIR)
all: multiboot.bin multiboot_dma.bin linuxboot.bin linuxboot_dma.bin kvmvapic.bin pvh.bin
# Dummy command so that make thinks it has done something
@true
include ../../config-host.mak
CFLAGS = -O2 -g
quiet-command = $(if $(V),$1,$(if $(2),@printf " %-7s %s\n" $2 $3 && $1, @$1))
cc-option = $(if $(shell $(CC) $1 -c -o /dev/null -xc /dev/null >/dev/null 2>&1 && echo OK), $1, $2)
override CFLAGS += -march=i486 -Wall
# If -fcf-protection is enabled in flags or compiler defaults that will
# conflict with -march=i486
override CFLAGS += $(call cc-option, -fcf-protection=none)
# Flags for dependency generation
override CPPFLAGS += -MMD -MP -MT $@ -MF $(@D)/$(*F).d
override CFLAGS += $(filter -W%, $(QEMU_CFLAGS))
override CFLAGS += $(CFLAGS_NOPIE) -ffreestanding -I$(TOPSRC_DIR)/include
override CFLAGS += $(call cc-option, -fno-stack-protector)
override CFLAGS += $(call cc-option, -m16)
ifeq ($(filter -m16, $(CFLAGS)),)
# Attempt to work around compilers that lack -m16 (GCC <= 4.8, clang <= ??)
# On GCC we add -fno-toplevel-reorder to keep the order of asm blocks with
# respect to the rest of the code. clang does not have -fno-toplevel-reorder,
# but it places all asm blocks at the beginning and we're relying on it for
# the option ROM header. So just force clang not to use the integrated
# assembler, which doesn't support .code16gcc.
override CFLAGS += $(call cc-option, -fno-toplevel-reorder)
override CFLAGS += $(call cc-option, -no-integrated-as)
override CFLAGS += -m32 -include $(SRC_DIR)/code16gcc.h
endif
Wa = -Wa,
override ASFLAGS += -32
override CFLAGS += $(call cc-option, $(Wa)-32)
LD_I386_EMULATION ?= elf_i386
override LDFLAGS = -m $(LD_I386_EMULATION) -T $(SRC_DIR)/flat.lds
pvh.img: pvh.o pvh_main.o
%.o: %.S
$(call quiet-command,$(CPP) $(CPPFLAGS) -c -o - $< | $(AS) $(ASFLAGS) -o $@,"AS","$@")
%.o: %.c
$(call quiet-command,$(CC) $(CPPFLAGS) $(CFLAGS) -c $< -o $@,"CC","$@")
%.img: %.o
$(call quiet-command,$(LD) $(LDFLAGS) -s -o $@ $^,"BUILD","$@")
%.raw: %.img
$(call quiet-command,$(OBJCOPY) -O binary -j .text $< $@,"BUILD","$@")
%.bin: %.raw
$(call quiet-command,$(PYTHON) $(TOPSRC_DIR)/scripts/signrom.py $< $@,"SIGN","$@")
include $(wildcard *.d)
clean:
rm -f *.o *.d *.raw *.img *.bin *~
# suppress auto-removal of intermediate files
.SECONDARY:
.PHONY: all clean