linux/tools/objtool/Makefile
Vasily Gorbik 2486baae2c objtool: Allow nested externs to enable BUILD_BUG()
Currently BUILD_BUG() macro is expanded to smth like the following:
   do {
           extern void __compiletime_assert_0(void)
                   __attribute__((error("BUILD_BUG failed")));
           if (!(!(1)))
                   __compiletime_assert_0();
   } while (0);

If used in a function body this obviously would produce build errors
with -Wnested-externs and -Werror.

Build objtool with -Wno-nested-externs to enable BUILD_BUG() usage.

Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
2020-10-06 09:32:13 -05:00

85 lines
2.2 KiB
Makefile

# SPDX-License-Identifier: GPL-2.0
include ../scripts/Makefile.include
include ../scripts/Makefile.arch
# always use the host compiler
ifneq ($(LLVM),)
HOSTAR ?= llvm-ar
HOSTCC ?= clang
HOSTLD ?= ld.lld
else
HOSTAR ?= ar
HOSTCC ?= gcc
HOSTLD ?= ld
endif
AR = $(HOSTAR)
CC = $(HOSTCC)
LD = $(HOSTLD)
ifeq ($(srctree),)
srctree := $(patsubst %/,%,$(dir $(CURDIR)))
srctree := $(patsubst %/,%,$(dir $(srctree)))
endif
SUBCMD_SRCDIR = $(srctree)/tools/lib/subcmd/
LIBSUBCMD_OUTPUT = $(if $(OUTPUT),$(OUTPUT),$(CURDIR)/)
LIBSUBCMD = $(LIBSUBCMD_OUTPUT)libsubcmd.a
OBJTOOL := $(OUTPUT)objtool
OBJTOOL_IN := $(OBJTOOL)-in.o
LIBELF_FLAGS := $(shell pkg-config libelf --cflags 2>/dev/null)
LIBELF_LIBS := $(shell pkg-config libelf --libs 2>/dev/null || echo -lelf)
all: $(OBJTOOL)
INCLUDES := -I$(srctree)/tools/include \
-I$(srctree)/tools/arch/$(HOSTARCH)/include/uapi \
-I$(srctree)/tools/arch/$(SRCARCH)/include \
-I$(srctree)/tools/objtool/arch/$(SRCARCH)/include
WARNINGS := $(EXTRA_WARNINGS) -Wno-switch-default -Wno-switch-enum -Wno-packed -Wno-nested-externs
CFLAGS := -Werror $(WARNINGS) $(KBUILD_HOSTCFLAGS) -g $(INCLUDES) $(LIBELF_FLAGS)
LDFLAGS += $(LIBELF_LIBS) $(LIBSUBCMD) $(KBUILD_HOSTLDFLAGS)
# Allow old libelf to be used:
elfshdr := $(shell echo '$(pound)include <libelf.h>' | $(CC) $(CFLAGS) -x c -E - | grep elf_getshdr)
CFLAGS += $(if $(elfshdr),,-DLIBELF_USE_DEPRECATED)
AWK = awk
SUBCMD_CHECK := n
SUBCMD_ORC := n
ifeq ($(SRCARCH),x86)
SUBCMD_CHECK := y
SUBCMD_ORC := y
endif
ifeq ($(SUBCMD_ORC),y)
CFLAGS += -DINSN_USE_ORC
endif
export SUBCMD_CHECK SUBCMD_ORC
export srctree OUTPUT CFLAGS SRCARCH AWK
include $(srctree)/tools/build/Makefile.include
$(OBJTOOL_IN): fixdep FORCE
@$(CONFIG_SHELL) ./sync-check.sh
@$(MAKE) $(build)=objtool
$(OBJTOOL): $(LIBSUBCMD) $(OBJTOOL_IN)
$(QUIET_LINK)$(CC) $(OBJTOOL_IN) $(LDFLAGS) -o $@
$(LIBSUBCMD): fixdep FORCE
$(Q)$(MAKE) -C $(SUBCMD_SRCDIR) OUTPUT=$(LIBSUBCMD_OUTPUT)
clean:
$(call QUIET_CLEAN, objtool) $(RM) $(OBJTOOL)
$(Q)find $(OUTPUT) -name '*.o' -delete -o -name '\.*.cmd' -delete -o -name '\.*.d' -delete
$(Q)$(RM) $(OUTPUT)arch/x86/inat-tables.c $(OUTPUT)fixdep
FORCE:
.PHONY: clean FORCE