linux/init
Masahiro Yamada b1992c3772 kbuild: use $(src) instead of $(srctree)/$(src) for source directory
Kbuild conventionally uses $(obj)/ for generated files, and $(src)/ for
checked-in source files. It is merely a convention without any functional
difference. In fact, $(obj) and $(src) are exactly the same, as defined
in scripts/Makefile.build:

    src := $(obj)

When the kernel is built in a separate output directory, $(src) does
not accurately reflect the source directory location. While Kbuild
resolves this discrepancy by specifying VPATH=$(srctree) to search for
source files, it does not cover all cases. For example, when adding a
header search path for local headers, -I$(srctree)/$(src) is typically
passed to the compiler.

This introduces inconsistency between upstream and downstream Makefiles
because $(src) is used instead of $(srctree)/$(src) for the latter.

To address this inconsistency, this commit changes the semantics of
$(src) so that it always points to the directory in the source tree.

Going forward, the variables used in Makefiles will have the following
meanings:

  $(obj)     - directory in the object tree
  $(src)     - directory in the source tree  (changed by this commit)
  $(objtree) - the top of the kernel object tree
  $(srctree) - the top of the kernel source tree

Consequently, $(srctree)/$(src) in upstream Makefiles need to be replaced
with $(src).

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
2024-05-10 04:34:52 +09:00
..
.gitignore kbuild: build init/built-in.a just once 2022-09-29 04:40:15 +09:00
build-version kbuild: build init/built-in.a just once 2022-09-29 04:40:15 +09:00
calibrate.c
do_mounts_initrd.c init: pass root_device_name explicitly 2023-06-05 10:55:20 -06:00
do_mounts_rd.c init: add an init_unlink helper 2020-07-31 08:17:52 +02:00
do_mounts.c init: flush async file closing 2024-02-08 18:41:03 +01:00
do_mounts.h init: flush async file closing 2024-02-08 18:41:03 +01:00
init_task.c rcu-tasks: Initialize data to eliminate RCU-tasks/do_exit() deadlocks 2024-02-25 14:21:43 -08:00
initramfs.c init: open output files from cpio unpacking with O_LARGEFILE 2024-04-05 11:21:30 -07:00
Kconfig RISC-V Patches for the 6.9 Merge Window 2024-03-22 10:41:13 -07:00
main.c init/main.c: Fix potential static_command_line memory overflow 2024-04-13 00:59:36 +09:00
Makefile kbuild: use $(src) instead of $(srctree)/$(src) for source directory 2024-05-10 04:34:52 +09:00
noinitramfs.c init: move usermodehelper_enable() to populate_rootfs() 2021-09-08 11:50:27 -07:00
version-timestamp.c init/version-timestamp.c: remove unneeded #include <linux/version.h> 2023-01-09 07:34:38 +09:00
version.c init/version.c: Replace strlcpy with strscpy 2023-09-22 09:50:56 -07:00