kbuild: use $(srctree) instead of KBUILD_SRC to check out-of-tree build
KBUILD_SRC was conventionally used for some different purposes:
[1] To remember the source tree path
[2] As a flag to check if sub-make is already done
[3] As a flag to check if Kbuild runs out of tree
For [1], we do not need to remember it because the top Makefile
can compute it by $(realpath $(dir $(lastword $(MAKEFILE_LIST))))
[2] has been replaced with self-commenting 'sub_make_done'.
For [3], we can distinguish in-tree/out-of-tree by comparing
$(srctree) and '.'
This commit converts [3] to prepare for the KBUILD_SRC removal.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
diff --git a/Makefile b/Makefile
index 4929c1f..72fad44 100644
--- a/Makefile
+++ b/Makefile
@@ -448,7 +448,7 @@
LINUXINCLUDE := \
-I$(srctree)/arch/$(SRCARCH)/include \
-I$(objtree)/arch/$(SRCARCH)/include/generated \
- $(if $(KBUILD_SRC), -I$(srctree)/include) \
+ $(if $(filter .,$(srctree)),,-I$(srctree)/include) \
-I$(objtree)/include \
$(USERINCLUDE)
@@ -509,7 +509,7 @@
# At the same time when output Makefile generated, generate .gitignore to
# ignore whole output directory
outputmakefile:
-ifneq ($(KBUILD_SRC),)
+ifneq ($(srctree),.)
$(Q)ln -fsn $(srctree) source
$(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile $(srctree)
$(Q)test -e .gitignore || \
@@ -1089,7 +1089,7 @@
# and if so do:
# 1) Check that make has not been executed in the kernel src $(srctree)
prepare3: include/config/kernel.release
-ifneq ($(KBUILD_SRC),)
+ifneq ($(srctree),.)
@$(kecho) ' Using $(srctree) as source for kernel'
$(Q)if [ -f $(srctree)/.config -o -d $(srctree)/include/config ]; then \
echo >&2 " $(srctree) is not clean, please run 'make mrproper'"; \
diff --git a/scripts/Makefile.build b/scripts/Makefile.build
index 76ca30c..9dddfb6 100644
--- a/scripts/Makefile.build
+++ b/scripts/Makefile.build
@@ -501,7 +501,7 @@
-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
-ifneq ($(KBUILD_SRC),)
+ifneq ($(srctree),.)
# Create directories for object files if they do not exist
obj-dirs := $(sort $(obj) $(patsubst %/,%, $(dir $(targets))))
# If targets exist, their directories apparently exist. Skip mkdir.
diff --git a/scripts/Makefile.host b/scripts/Makefile.host
index a115259..73b8041 100644
--- a/scripts/Makefile.host
+++ b/scripts/Makefile.host
@@ -71,7 +71,7 @@
__hostcxx_flags = $(_hostcxx_flags)
ifeq ($(KBUILD_EXTMOD),)
-ifneq ($(KBUILD_SRC),)
+ifneq ($(srctree),.)
__hostc_flags = -I$(obj) $(call flags,_hostc_flags)
__hostcxx_flags = -I$(obj) $(call flags,_hostcxx_flags)
endif
diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
index 8a1f64f..41e98fa 100644
--- a/scripts/Makefile.lib
+++ b/scripts/Makefile.lib
@@ -144,7 +144,7 @@
# If building the kernel in a separate objtree expand all occurrences
# of -Idir to -I$(srctree)/dir except for absolute paths (starting with '/').
ifeq ($(KBUILD_EXTMOD),)
-ifneq ($(KBUILD_SRC),)
+ifneq ($(srctree),.)
# -I$(obj) locates generated .h files
# $(call addtree,-I$(obj)) locates .h files in srctree, from generated .c files
diff --git a/scripts/Makefile.modbuiltin b/scripts/Makefile.modbuiltin
index a072a42..ea90a90 100644
--- a/scripts/Makefile.modbuiltin
+++ b/scripts/Makefile.modbuiltin
@@ -15,7 +15,7 @@
include scripts/Kbuild.include
-ifneq ($(KBUILD_SRC),)
+ifneq ($(srctree),.)
# Create output directory if not already present
_dummy := $(shell [ -d $(obj) ] || mkdir -p $(obj))
endif
diff --git a/scripts/gdb/linux/Makefile b/scripts/gdb/linux/Makefile
index 3df395a..9fd3d8e 100644
--- a/scripts/gdb/linux/Makefile
+++ b/scripts/gdb/linux/Makefile
@@ -1,6 +1,6 @@
# SPDX-License-Identifier: GPL-2.0
-ifneq ($(KBUILD_SRC),)
+ifneq ($(srctree),.)
symlinks := $(patsubst $(srctree)/$(src)/%,%,$(wildcard $(srctree)/$(src)/*.py))
diff --git a/scripts/tags.sh b/scripts/tags.sh
index f470d99..6a55180 100755
--- a/scripts/tags.sh
+++ b/scripts/tags.sh
@@ -19,7 +19,7 @@
# Do not use full path if we do not use O=.. builds
# Use make O=. {tags|cscope}
# to force full paths for a non-O= build
-if [ "${KBUILD_SRC}" = "" ]; then
+if [ "${srctree}" = "." ]; then
tree=
else
tree=${srctree}/