linux/Documentation
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
..
ABI Char/Misc and other driver subsystem updates for 6.9-rc1 2024-03-21 13:21:31 -07:00
accel
accounting
admin-guide x86/bugs: Remove CONFIG_BHI_MITIGATION_AUTO and spectre_bhi=auto 2024-04-12 12:05:54 +02:00
arch Documentation/x86: Fix title underline length 2024-03-25 11:29:16 +01:00
block
bpf bpf, docs: Rename legacy conformance group to packet 2024-03-04 14:31:06 +01:00
cdrom
core-api workqueue: Changes for v6.9 2024-03-11 12:50:42 -07:00
cpu-freq
crypto
dev-tools Documentation: dev-tools: Add link to RV docs 2024-03-29 08:27:21 -06:00
devicetree kbuild: use $(src) instead of $(srctree)/$(src) for source directory 2024-05-10 04:34:52 +09:00
doc-guide docs: drop the version constraints for sphinx and dependencies 2024-03-03 08:17:20 -07:00
driver-api virtio: store owner from modules with register_virtio_driver() 2024-04-08 04:11:04 -04:00
fault-injection Fixed case issue with 'fault-injection' in documentation 2024-02-21 13:44:21 -07:00
fb
features
filesystems Documentation: filesystems: Add bcachefs toctree 2024-04-06 13:50:26 -04:00
firmware_class
firmware-guide More ACPI updates for 6.9-rc1 2024-03-19 11:15:14 -07:00
fpga
gpu drm-misc-next for v6.9: 2024-02-26 09:51:49 +01:00
hid
hwmon hwmon: (aspeed-g6-pwm-tacho): Support for ASPEED g6 PWM/Fan tach 2024-03-07 10:50:16 -08:00
i2c Documentation: i2c: Document that client auto-detection is a legacy mechanism 2024-03-07 09:42:09 +01:00
iio docs: iio: add documentation for adis16475 driver 2024-02-28 19:26:36 +00:00
images
infiniband
input
isdn
kbuild kbuild: use $(src) instead of $(srctree)/$(src) for source directory 2024-05-10 04:34:52 +09:00
kernel-hacking
leds
litmus-tests
livepatch
locking
maintainer
mhi
misc-devices
mm mm,page_owner: fix refcount imbalance 2024-04-16 15:39:49 -07:00
netlabel
netlink Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2024-03-11 20:38:36 -07:00
networking Documentation: Add documentation for eswitch attribute 2024-03-28 18:20:08 -07:00
nvdimm
nvme
PCI
pcmcia
peci
power Documentation: power: Fix typo in suspend and interrupts doc 2024-03-13 20:51:11 +01:00
process Documentation: embargoed-hardware-issues.rst: Add myself for Power 2024-04-11 15:21:18 +02:00
RCU A moderatly busy cycle for development this time around. 2024-03-12 15:18:34 -07:00
rust arm64 updates for 6.9: 2024-03-14 15:35:42 -07:00
scheduler A single update for the documentation of the base_slice_ns tunable to 2024-03-24 11:11:05 -07:00
scsi
security
sound
sphinx docs: drop the version constraints for sphinx and dependencies 2024-03-03 08:17:20 -07:00
sphinx-static
spi spi: docs: spidev: fix echo command format 2024-03-19 18:37:55 +00:00
staging
target
tee
timers
tools tools/rtla: Add -U/--user-load option to timerlat 2024-03-20 05:39:06 +01:00
trace tracing/user_events: Document multi-format flag 2024-03-18 10:13:16 -04:00
translations - Sumanth Korikkar has taught s390 to allocate hotplug-time page frames 2024-03-14 17:43:30 -07:00
usb
userspace-api media updates for v6.9-rc1 2024-03-15 11:36:54 -07:00
virt Documentation: kvm/sev: clarify usage of KVM_MEMORY_ENCRYPT_OP 2024-03-18 19:03:53 -04:00
w1
watchdog
wmi platform/x86: wmi: Update documentation regarding _WED 2024-02-27 14:44:31 +02:00
.gitignore
atomic_bitops.txt
atomic_t.txt
Changes
CodingStyle
conf.py docs: Restore "smart quotes" for quotes 2024-02-28 15:48:18 -07:00
docutils.conf
dontdiff
index.rst A moderatly busy cycle for development this time around. 2024-03-12 15:18:34 -07:00
Kconfig
Makefile kbuild: use $(src) instead of $(srctree)/$(src) for source directory 2024-05-10 04:34:52 +09:00
memory-barriers.txt
SubmittingPatches
subsystem-apis.rst