linux-yocto/Kbuild
Masahiro Yamada 8a58e1628c kbuild: do not add $(bounds-file) and $(offsets-file) to targets
$(always) is added to targets by scripts/Makefile.build.
Moreover, filechk does not need .*.cmd files.

Adding these two files to targets is redundant.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2015-04-02 16:33:27 +02:00

2.1 KiB

Kbuild for top-level directory of the kernel

This file takes care of the following:

1) Generate bounds.h

2) Generate asm-offsets.h (may need bounds.h)

3) Check for missing system calls

Default sed regexp - multiline due to syntax constraints

define sed-y "/^->/{s:->#.*:/* \1 /:;
s:^->[^ ]* [$$#]
[-0-9]* .*:#define \1 \2 /* \3 /:;
s:^->[^ ]* [$$#]
[^ ]* .*:#define \1 \2 /* \3 */:;
s:->::; p;}" endef

Use filechk to avoid rebuilds when a header changes, but the resulting file

does not

define filechk_offsets (set -e;
echo "#ifndef $2";
echo "#define $2";
echo "/*";
echo " * DO NOT MODIFY.";
echo " *";
echo " * This file was generated by Kbuild";
echo " */";
echo "";
sed -ne $(sed-y);
echo "";
echo "#endif" ) endef

1) Generate bounds.h

bounds-file := include/generated/bounds.h

always := $(bounds-file) targets := kernel/bounds.s

We use internal kbuild rules to avoid the "is up to date" message from make

kernel/bounds.s: kernel/bounds.c FORCE $(Q)mkdir -p $(dir $@) $(call if_changed_dep,cc_s_c)

$(obj)/$(bounds-file): kernel/bounds.s FORCE $(call filechk,offsets,LINUX_BOUNDS_H)

2) Generate asm-offsets.h

offsets-file := include/generated/asm-offsets.h

always += $(offsets-file) targets += arch/$(SRCARCH)/kernel/asm-offsets.s

We use internal kbuild rules to avoid the "is up to date" message from make

arch/$(SRCARCH)/kernel/asm-offsets.s: arch/$(SRCARCH)/kernel/asm-offsets.c
$(obj)/$(bounds-file) FORCE $(Q)mkdir -p $(dir $@) $(call if_changed_dep,cc_s_c)

$(obj)/$(offsets-file): arch/$(SRCARCH)/kernel/asm-offsets.s FORCE $(call filechk,offsets,ASM_OFFSETS_H)

3) Check for missing system calls

always += missing-syscalls targets += missing-syscalls

quiet_cmd_syscalls = CALL $< cmd_syscalls = $(CONFIG_SHELL) $< $(CC) $(c_flags) $(missing_syscalls_flags)

missing-syscalls: scripts/checksyscalls.sh $(offsets-file) FORCE $(call cmd,syscalls)

Keep these two files during make clean

no-clean-files := $(bounds-file) $(offsets-file)