mirror of
https://github.com/brain-hackers/u-boot-brain
synced 2024-06-09 23:36:03 +09:00
![Masahiro Yamada](/assets/img/avatar_default.png)
This commit changes the working directory where the build process occurs. Before this commit, build process occurred under the source tree for both in-tree and out-of-tree build. That's why we needed to add $(obj) prefix to all generated files in makefiles like follows: $(obj)u-boot.bin: $(obj)u-boot Here, $(obj) is empty for in-tree build, whereas it points to the output directory for out-of-tree build. And our old build system changes the current working directory with "make -C <sub-dir>" syntax when descending into the sub-directories. On the other hand, Kbuild uses a different idea to handle out-of-tree build and directory descending. The build process of Kbuild always occurs under the output tree. When "O=dir/to/store/output/files" is given, the build system changes the current working directory to that directory and restarts the make. Kbuild uses "make -f $(srctree)/scripts/Makefile.build obj=<sub-dir>" syntax for descending into sub-directories. (We can write it like "make $(obj)=<sub-dir>" with a shorthand.) This means the current working directory is always the top of the output directory. Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com> Tested-by: Gerhard Sittig <gsi@denx.de>
17 lines
466 B
Makefile
17 lines
466 B
Makefile
#
|
|
# Copyright (c) 2011 The Chromium OS Authors.
|
|
#
|
|
# (C) Copyright 2000-2003
|
|
# Wolfgang Denk, DENX Software Engineering, wd@denx.de.
|
|
#
|
|
# SPDX-License-Identifier: GPL-2.0+
|
|
#
|
|
|
|
obj-y := cpu.o os.o start.o state.o
|
|
|
|
# os.c is build in the system environment, so needs standard includes
|
|
$(obj)/os.o: CFLAGS := $(filter-out -nostdinc,\
|
|
$(patsubst -I%,-idirafter%,$(CFLAGS)))
|
|
$(obj)/.depend.os: CPPFLAGS := $(filter-out -nostdinc,\
|
|
$(patsubst -I%,-idirafter%,$(CPPFLAGS)))
|