blob: 84019814f33f09323bcb9b50e8c3b1cae19c1696 [file] [log] [blame]
# SPDX-License-Identifier: GPL-2.0-only
PHONY := __default
__default: vmlinux.o
include include/config/auto.conf
include $(srctree)/scripts/Kbuild.include
# for objtool
include $(srctree)/scripts/Makefile.lib
# Generate a linker script to ensure correct ordering of initcalls for Clang LTO
# ---------------------------------------------------------------------------
quiet_cmd_gen_initcalls_lds = GEN $@
cmd_gen_initcalls_lds = \
$(PYTHON3) $(srctree)/scripts/jobserver-exec \
$(PERL) $(real-prereqs) > $@ $(srctree)/scripts/ \
$(call if_changed,gen_initcalls_lds)
targets :=
initcalls-lds :=
# objtool for vmlinux.o
# ---------------------------------------------------------------------------
# For LTO and IBT, objtool doesn't run on individual translation units.
# Run everything on vmlinux instead.
objtool-enabled := $(or $(delay-objtool),$(CONFIG_NOINSTR_VALIDATION))
# Reuse objtool_args defined in scripts/Makefile.lib if LTO or IBT is enabled.
# Add some more flags as needed.
# --no-unreachable and --link might be added twice, but it is fine.
# Expand objtool_args to a simple variable to avoid circular reference.
objtool_args := \
$(if $(delay-objtool),$(objtool_args)) \
$(if $(CONFIG_NOINSTR_VALIDATION), --noinstr $(if $(CONFIG_CPU_UNRET_ENTRY), --unret)) \
$(if $(CONFIG_GCOV_KERNEL), --no-unreachable) \
# Link of vmlinux.o used for section mismatch analysis
# ---------------------------------------------------------------------------
quiet_cmd_ld_vmlinux.o = LD $@
cmd_ld_vmlinux.o = \
$(LD) ${KBUILD_LDFLAGS} -r -o $@ \
$(addprefix -T , $(initcalls-lds)) \
--whole-archive $(KBUILD_VMLINUX_OBJS) --no-whole-archive \
--start-group $(KBUILD_VMLINUX_LIBS) --end-group \
define rule_ld_vmlinux.o
$(call cmd_and_savecmd,ld_vmlinux.o)
$(call cmd,gen_objtooldep)
vmlinux.o: $(initcalls-lds) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS) FORCE
$(call if_changed_rule,ld_vmlinux.o)
targets += vmlinux.o
# Add FORCE to the prequisites of a target to force it to be always rebuilt.
# ---------------------------------------------------------------------------
# Read all saved command lines and dependencies for the $(targets) we
# may be building above, using $(if_changed{,_dep}). As an
# optimization, we don't need to read them if the target does not
# exist, we will rebuild anyway in that case.
existing-targets := $(wildcard $(sort $(targets)))
-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)