scripts/Makefile.build

Source file repositories/reference/linux-study-clean/scripts/Makefile.build

File Facts

System
Linux kernel
Corpus path
scripts/Makefile.build
Extension
.build
Size
21300 bytes
Lines
597
Domain
Support Tooling And Documentation
Bucket
scripts
Inferred role
Support Tooling And Documentation: exported/initcall integration point
Status
integration implementation candidate

Why This File Exists

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

Dependency Surface

Detected Declarations

Annotated Snippet

# SPDX-License-Identifier: GPL-2.0
# ==========================================================================
# Building
# ==========================================================================

src := $(srcroot)/$(obj)

PHONY := $(obj)/
$(obj)/:

# Init all relevant variables used in kbuild files so
# 1) they have correct type
# 2) they do not inherit any value from the environment
obj-y :=
obj-m :=
lib-y :=
lib-m :=
always-y :=
always-m :=
targets :=
subdir-y :=
subdir-m :=
asflags-y  :=
ccflags-y  :=
rustflags-y :=
cppflags-y :=
ldflags-y  :=

subdir-asflags-y :=
subdir-ccflags-y :=

# Read auto.conf if it exists, otherwise ignore
-include $(objtree)/include/config/auto.conf

include $(srctree)/scripts/Kbuild.include
include $(srctree)/scripts/Makefile.compiler
include $(kbuild-file)
include $(srctree)/scripts/Makefile.lib

# flags that take effect in current and sub directories
KBUILD_AFLAGS += $(subdir-asflags-y)
KBUILD_CFLAGS += $(subdir-ccflags-y)
KBUILD_RUSTFLAGS += $(subdir-rustflags-y)

# Figure out what we need to build from the various variables
# ===========================================================================

# When an object is listed to be built compiled-in and modular,
# only build the compiled-in version
obj-m := $(filter-out $(obj-y),$(obj-m))

# Libraries are always collected in one lib file.
# Filter out objects already built-in
lib-y := $(filter-out $(obj-y), $(sort $(lib-y) $(lib-m)))

# Subdirectories we need to descend into
subdir-ym := $(sort $(subdir-y) $(subdir-m) \
			$(patsubst %/,%, $(filter %/, $(obj-y) $(obj-m))))

# Handle objects in subdirs:
# - If we encounter foo/ in $(obj-y), replace it by foo/built-in.a and
#   foo/modules.order
# - If we encounter foo/ in $(obj-m), replace it by foo/modules.order
#
# Generate modules.order to determine modorder. Unfortunately, we don't have
# information about ordering between -y and -m subdirs. Just put -y's first.

ifdef need-modorder
obj-m := $(patsubst %/,%/modules.order, $(filter %/, $(obj-y)) $(obj-m))
else

Annotation

Implementation Notes