kconfig / kbuild: Re-sync with Linux 4.20

Align Kconfig and Kbuild logic to Linux 4.20 release with minimal impact
on files outside of this scope.

Our previous Kconfig sync was done by commit 587e4a4296 ("kconfig /
kbuild: Re-sync with Linux 4.19").

As part of this re-sync, a few related changes from previous Linux
releases were found to have been missed and merged in, and are not in
the following list.

The imported Linux commits are:

[From prior to v4.19]
b1e0d8b70fa3 kbuild: Fix gcc -x syntax
a4353898980c kconfig: add CC_IS_GCC and GCC_VERSION
469cb7376c06 kconfig: add CC_IS_CLANG and CLANG_VERSION

[From v4.19 to v4.20]
487c7c7702ab kbuild: prefix Makefile.dtbinst path with $(srctree) unconditionally
0d91bf584fe5 kbuild: remove old check for CFLAGS use
25815cf5ffec kbuild: hide most of targets when running config or mixed targets
00d78ab2ba75 kbuild: remove dead code in cmd_files calculation in top Makefile
23066c3f4e21 Compiler Attributes: enable -Wstringop-truncation on W=1 (gcc >= 8)
37c8a5fafa3b kbuild: consolidate Devicetree dtb build rules
80463f1b7bf9 kbuild: add --include-dir flag only for out-of-tree build
77ec0c20c7e0 kbuild: remove VERSION and PATCHLEVEL from $(objtree)/Makefile
74bc0c09b2da kbuild: remove user ID check in scripts/mkmakefile
4fd61277f662 kbuild: do not pass $(objtree) to scripts/mkmakefile
80d0dda3a4e5 kbuild: simplify command line creation in scripts/mkmakefile
fb073a4b473e kbuild: add -Wno-pointer-sign flag unconditionally
9df3e7a7d7d6 kbuild: add -Wno-unused-but-set-variable flag unconditionally
69ea912fda74 kbuild: remove unneeded link_multi_deps
7d0ea2524202 kbuild: use 'else ifeq' for checksrc to improve readability
04c459d20448 kconfig: remove oldnoconfig target
0085b4191f3e kconfig: remove silentoldconfig target
3f80babd9ca4 kbuild: remove unused cc-fullversion variable
2cd3faf87d2d merge_config.sh: Allow to define config prefix
076f421da5d4 kbuild: replace cc-name test with CONFIG_CC_IS_CLANG
6bbe4385d035 kconfig: merge_config: avoid false positive matches from comment lines

[From post v4.20]
885480b08469 Makefile: Move -Wno-unused-but-set-variable out of GCC only block

There are a number of changes related to additional warnings as well as
being able to drop cc-name entirely that have been omitted for now as
additional work is required first.

Cc: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Tom Rini <trini@konsulko.com>
This commit is contained in:
Tom Rini 2021-06-17 18:07:25 -04:00
parent e57c7c5c42
commit 473fc279c8
12 changed files with 124 additions and 99 deletions

15
Kconfig
View File

@ -57,6 +57,21 @@ config LOCALVERSION_AUTO
which is done within the script "scripts/setlocalversion".)
config CC_IS_GCC
def_bool $(success,$(CC) --version | head -n 1 | grep -q gcc)
config GCC_VERSION
int
default $(shell,$(srctree)/scripts/gcc-version.sh -p $(CC) | sed 's/^0*//') if CC_IS_GCC
default 0
config CC_IS_CLANG
def_bool $(success,$(CC) --version | head -n 1 | grep -q clang)
config CLANG_VERSION
int
default $(shell,$(srctree)/scripts/clang-version.sh $(CC))
config CC_OPTIMIZE_FOR_SIZE
bool "Optimize for size"
default y

View File

@ -12,10 +12,9 @@ NAME =
# Comments in this file are targeted only to the developer, do not
# expect to learn how to build the kernel reading this file.
# o Do not use make's built-in rules and variables
# (this increases performance and avoids hard-to-debug behaviour);
# o Look for make include files relative to root of kernel src
MAKEFLAGS += -rR --include-dir=$(CURDIR)
# Do not use make's built-in rules and variables
# (this increases performance and avoids hard-to-debug behaviour)
MAKEFLAGS += -rR
# Determine target architecture for the sandbox
include include/host_arch.h
@ -162,6 +161,13 @@ KBUILD_OUTPUT := $(shell mkdir -p $(KBUILD_OUTPUT) && cd $(KBUILD_OUTPUT) \
$(if $(KBUILD_OUTPUT),, \
$(error failed to create output directory "$(saved-output)"))
# Look for make include files relative to root of kernel src
#
# This does not become effective immediately because MAKEFLAGS is re-parsed
# once after the Makefile is read. It is OK since we are going to invoke
# 'sub-make' below.
MAKEFLAGS += --include-dir=$(CURDIR)
PHONY += $(MAKECMDGOALS) sub-make
$(filter-out _all sub-make $(CURDIR)/Makefile, $(MAKECMDGOALS)) _all: sub-make
@ -492,8 +498,7 @@ PHONY += outputmakefile
outputmakefile:
ifneq ($(KBUILD_SRC),)
$(Q)ln -fsn $(srctree) source
$(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile \
$(srctree) $(objtree) $(VERSION) $(PATCHLEVEL)
$(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkmakefile $(srctree)
endif
# To make sure we do not include .config for any of the *config targets
@ -572,7 +577,7 @@ else
# Carefully list dependencies so we do not try to build scripts twice
# in parallel
PHONY += scripts
scripts: scripts_basic include/config/auto.conf
scripts: scripts_basic scripts_dtc include/config/auto.conf
$(Q)$(MAKE) $(build)=$(@)
ifeq ($(dot-config),1)
@ -709,6 +714,9 @@ KBUILD_CFLAGS += $(call cc-option,-fno-stack-protector)
endif
KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks)
# disable pointer signed / unsigned warnings in gcc 4.0
KBUILD_CFLAGS += -Wno-pointer-sign
# disable stringop warnings in gcc 8+
KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)
@ -739,7 +747,7 @@ endif
KBUILD_CFLAGS += $(call cc-option,-Wno-format-nonliteral)
KBUILD_CFLAGS += $(call cc-disable-warning, address-of-packed-member)
ifeq ($(cc-name),clang)
ifdef CONFIG_CC_IS_CLANG
KBUILD_CPPFLAGS += $(call cc-option,-Qunused-arguments,)
KBUILD_CFLAGS += $(call cc-disable-warning, format-invalid-specifier)
KBUILD_CFLAGS += $(call cc-disable-warning, gnu)
@ -751,12 +759,11 @@ KBUILD_CFLAGS += $(call cc-disable-warning, tautological-compare)
# See modpost pattern 2
KBUILD_CFLAGS += $(call cc-option, -mno-global-merge,)
KBUILD_CFLAGS += $(call cc-option, -fcatch-undefined-behavior)
else
endif
# These warnings generated too much noise in a regular build.
# Use make W=1 to enable them (see scripts/Makefile.extrawarn)
KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable)
endif
# Prohibit date/time macros, which would make the build non-deterministic
KBUILD_CFLAGS += $(call cc-option,-Werror=date-time)
@ -1946,6 +1953,35 @@ $(dt_h): $(srctree)/Makefile FORCE
$(defaultenv_h): $(CONFIG_DEFAULT_ENV_FILE:"%"=%) FORCE
$(call filechk,defaultenv.h)
# ---------------------------------------------------------------------------
# Devicetree files
ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
dtstree := arch/$(SRCARCH)/boot/dts
endif
ifneq ($(dtstree),)
%.dtb: prepare3 scripts_dtc
$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
PHONY += dtbs dtbs_install
dtbs: prepare3 scripts_dtc
$(Q)$(MAKE) $(build)=$(dtstree)
dtbs_install:
$(Q)$(MAKE) $(dtbinst)=$(dtstree)
ifdef CONFIG_OF_EARLY_FLATTREE
all: dtbs
endif
endif
PHONY += scripts_dtc
scripts_dtc: scripts_basic
$(Q)$(MAKE) $(build)=scripts/dtc
# ---------------------------------------------------------------------------
quiet_cmd_cpp_lds = LDS $@
cmd_cpp_lds = $(CPP) -Wp,-MD,$(depfile) $(cpp_flags) $(LDPPFLAGS) \
@ -2208,9 +2244,6 @@ PHONY += $(DOC_TARGETS)
$(DOC_TARGETS): scripts_basic FORCE
$(Q)$(MAKE) $(build)=doc $@
endif #ifeq ($(config-targets),1)
endif #ifeq ($(mixed-targets),1)
PHONY += checkstack ubootrelease ubootversion
checkstack:
@ -2298,13 +2331,15 @@ quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN $(wildcard $(rm-files))
# read all saved command lines
cmd_files := $(wildcard .*.cmd $(foreach f,$(sort $(targets)),$(dir $(f)).$(notdir $(f)).cmd))
cmd_files := $(wildcard .*.cmd)
ifneq ($(cmd_files),)
$(cmd_files): ; # Do not try to update included dependency files
include $(cmd_files)
endif
endif #ifeq ($(config-targets),1)
endif #ifeq ($(mixed-targets),1)
endif # skip-makefile
PHONY += FORCE

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@ -142,10 +142,6 @@ cc-name = $(shell $(CC) -v 2>&1 | grep -q "clang version" && echo clang || echo
# cc-version
cc-version = $(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-version.sh $(CC))
# cc-fullversion
cc-fullversion = $(shell $(CONFIG_SHELL) \
$(srctree)/scripts/gcc-version.sh -p $(CC))
# cc-ifversion
# Usage: EXTRA_CFLAGS += $(call cc-ifversion, -lt, 0402, -O1)
cc-ifversion = $(shell [ $(cc-version) $(1) $(2) ] && echo $(3) || echo $(4))
@ -193,7 +189,7 @@ modbuiltin := -f $(srctree)/scripts/Makefile.modbuiltin obj
# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.dtbinst obj=
# Usage:
# $(Q)$(MAKE) $(dtbinst)=dir
dtbinst := -f $(if $(KBUILD_SRC),$(srctree)/)scripts/Makefile.dtbinst obj
dtbinst := -f $(srctree)/scripts/Makefile.dtbinst obj
###
# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.clean obj=

View File

@ -48,9 +48,6 @@ include scripts/Makefile.uncmd_spl
include scripts/Kbuild.include
# For backward compatibility check that these variables do not change
save-cflags := $(CFLAGS)
# The filename Kbuild has precedence over Makefile
kbuild-dir := $(if $(filter /%,$(src)),$(src),$(srctree)/$(src))
kbuild-file := $(if $(wildcard $(kbuild-dir)/Kbuild),$(kbuild-dir)/Kbuild,$(kbuild-dir)/Makefile)
@ -61,13 +58,6 @@ asflags-y += $(PLATFORM_CPPFLAGS)
ccflags-y += $(PLATFORM_CPPFLAGS)
cppflags-y += $(PLATFORM_CPPFLAGS)
# If the save-* variables changed error out
ifeq ($(KBUILD_NOPEDANTIC),)
ifneq ("$(save-cflags)","$(CFLAGS)")
$(error CFLAGS was changed in "$(kbuild-file)". Fix it to use ccflags-y)
endif
endif
include scripts/Makefile.lib
# Do not include host rules unless needed
@ -99,14 +89,12 @@ __build: $(if $(KBUILD_BUILTIN),$(builtin-target) $(lib-target) $(extra-y)) \
@:
# Linus' kernel sanity checking tool
ifneq ($(KBUILD_CHECKSRC),0)
ifeq ($(KBUILD_CHECKSRC),2)
quiet_cmd_force_checksrc = CHECK $<
cmd_force_checksrc = $(CHECK) $(CHECKFLAGS) $(c_flags) $< ;
else
quiet_cmd_checksrc = CHECK $<
cmd_checksrc = $(CHECK) $(CHECKFLAGS) $(c_flags) $< ;
endif
ifeq ($(KBUILD_CHECKSRC),1)
quiet_cmd_checksrc = CHECK $<
cmd_checksrc = $(CHECK) $(CHECKFLAGS) $(c_flags) $< ;
else ifeq ($(KBUILD_CHECKSRC),2)
quiet_cmd_force_checksrc = CHECK $<
cmd_force_checksrc = $(CHECK) $(CHECKFLAGS) $(c_flags) $< ;
endif
# Do section mismatch analysis for each module/built-in.o
@ -369,21 +357,8 @@ $(lib-target): $(lib-y) FORCE
targets += $(lib-target)
endif
#
# Rule to link composite objects
#
# Composite objects are specified in kbuild makefile as follows:
# <composite-object>-objs := <list of .o files>
# or
# <composite-object>-y := <list of .o files>
link_multi_deps = \
$(filter $(addprefix $(obj)/, \
$($(subst $(obj)/,,$(@:.o=-objs))) \
$($(subst $(obj)/,,$(@:.o=-y)))), $^)
quiet_cmd_link_multi-y = AR $@
cmd_link_multi-y = rm -f $@; $(AR) cDPrsT$(KBUILD_ARFLAGS) $@ $(link_multi_deps)
cmd_link_multi-y = rm -f $@; $(AR) cDPrsT$(KBUILD_ARFLAGS) $@ $(filter %.o,$^)
quiet_cmd_link_multi-m = AR [M] $@
cmd_link_multi-m = $(cmd_link_multi-y)
@ -394,7 +369,7 @@ $(call multi_depend, $(multi-used-y), .o, -objs -y)
$(multi-used-m): FORCE
$(call if_changed,link_multi-m)
@{ echo $(@:.o=.ko); echo $(link_multi_deps); } > $(MODVERDIR)/$(@F:.o=.mod)
@{ echo $(@:.o=.ko); echo $(filter %.o,$^); } > $(MODVERDIR)/$(@F:.o=.mod)
$(call multi_depend, $(multi-used-m), .o, -objs -y)
targets += $(multi-used-y) $(multi-used-m)

View File

@ -11,6 +11,8 @@
# are not supported by all versions of the compiler
# ==========================================================================
KBUILD_CFLAGS += $(call cc-disable-warning, packed-not-aligned)
ifeq ("$(origin W)", "command line")
export KBUILD_ENABLE_EXTRA_GCC_CHECKS := $(W)
endif
@ -25,7 +27,11 @@ warning-1 += $(call cc-option, -Wmissing-prototypes)
warning-1 += -Wold-style-definition
warning-1 += $(call cc-option, -Wmissing-include-dirs)
warning-1 += $(call cc-option, -Wunused-but-set-variable)
warning-1 += $(call cc-option, -Wunused-const-variable)
warning-1 += $(call cc-option, -Wpacked-not-aligned)
warning-1 += $(call cc-option, -Wstringop-truncation)
warning-1 += $(call cc-disable-warning, missing-field-initializers)
warning-1 += $(call cc-disable-warning, sign-compare)
warning-2 := -Waggregate-return
warning-2 += -Wcast-align
@ -34,6 +40,9 @@ warning-2 += -Wnested-externs
warning-2 += -Wshadow
warning-2 += $(call cc-option, -Wlogical-op)
warning-2 += $(call cc-option, -Wmissing-field-initializers)
warning-2 += $(call cc-option, -Wsign-compare)
warning-2 += $(call cc-option, -Wmaybe-uninitialized)
warning-2 += $(call cc-option, -Wunused-macros)
warning-3 := -Wbad-function-cast
warning-3 += -Wcast-qual

View File

@ -320,7 +320,7 @@ quiet_cmd_dtc = DTC $@
# Bring in any U-Boot-specific include at the end of the file
cmd_dtc = mkdir -p $(dir ${dtc-tmp}) ; \
(cat $<; $(if $(u_boot_dtsi),echo '$(pound)include "$(u_boot_dtsi)"')) > $(pre-tmp); \
$(CPP) $(dtc_cpp_flags) -x assembler-with-cpp -o $(dtc-tmp) $(pre-tmp) ; \
$(HOSTCC) -E $(dtc_cpp_flags) -x assembler-with-cpp -o $(dtc-tmp) $(pre-tmp) ; \
$(DTC) -O dtb -o $@ -b 0 \
-i $(dir $<) $(DTC_FLAGS) \
-d $(depfile).dtc.tmp $(dtc-tmp) || \

23
scripts/clang-version.sh Executable file
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@ -0,0 +1,23 @@
#!/bin/sh
# SPDX-License-Identifier: GPL-2.0
#
# clang-version [-p] clang-command
#
# Prints the compiler version of `clang-command' in a canonical 4-digit form
# such as `0500' for clang-5.0 etc.
#
# With the -p option, prints the patchlevel as well, for example `050001' for
# clang-5.0.1 etc.
#
compiler="$*"
if ! ( $compiler --version | grep -q clang) ; then
echo 0
exit 1
fi
MAJOR=$(echo __clang_major__ | $compiler -E -x c - | tail -n 1)
MINOR=$(echo __clang_minor__ | $compiler -E -x c - | tail -n 1)
PATCHLEVEL=$(echo __clang_patchlevel__ | $compiler -E -x c - | tail -n 1)
printf "%d%02d%02d\\n" $MAJOR $MINOR $PATCHLEVEL

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@ -1,4 +1,5 @@
#!/bin/sh
# SPDX-License-Identifier: GPL-2.0
#
# gcc-version [-p] gcc-command
#
@ -22,10 +23,10 @@ if [ ${#compiler} -eq 0 ]; then
exit 1
fi
MAJOR=$(echo __GNUC__ | $compiler -E -xc - | tail -n 1)
MINOR=$(echo __GNUC_MINOR__ | $compiler -E -xc - | tail -n 1)
MAJOR=$(echo __GNUC__ | $compiler -E -x c - | tail -n 1)
MINOR=$(echo __GNUC_MINOR__ | $compiler -E -x c - | tail -n 1)
if [ "x$with_patchlevel" != "x" ] ; then
PATCHLEVEL=$(echo __GNUC_PATCHLEVEL__ | $compiler -E -xc - | tail -n 1)
PATCHLEVEL=$(echo __GNUC_PATCHLEVEL__ | $compiler -E -x c - | tail -n 1)
printf "%02d%02d%02d\\n" $MAJOR $MINOR $PATCHLEVEL
else
printf "%02d%02d\\n" $MAJOR $MINOR

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@ -74,21 +74,7 @@ PHONY += $(simple-targets)
$(simple-targets): $(obj)/conf
$< $(silent) --$@ $(Kconfig)
PHONY += oldnoconfig silentoldconfig savedefconfig defconfig
# oldnoconfig is an alias of olddefconfig, because people already are dependent
# on its behavior (sets new symbols to their default value but not 'n') with the
# counter-intuitive name.
oldnoconfig: olddefconfig
@echo " WARNING: \"oldnoconfig\" target will be removed after Linux 4.19"
@echo " Please use \"olddefconfig\" instead, which is an alias."
# We do not expect manual invokcation of "silentoldcofig" (or "syncconfig").
silentoldconfig: syncconfig
@echo " WARNING: \"silentoldconfig\" has been renamed to \"syncconfig\""
@echo " and is now an internal implementation detail."
@echo " What you want is probably \"oldconfig\"."
@echo " \"silentoldconfig\" will be removed after Linux 4.19"
PHONY += savedefconfig defconfig
savedefconfig: $(obj)/conf
$< $(silent) --$@=defconfig $(Kconfig)

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@ -460,12 +460,6 @@ static struct option long_opts[] = {
{"randconfig", no_argument, NULL, randconfig},
{"listnewconfig", no_argument, NULL, listnewconfig},
{"olddefconfig", no_argument, NULL, olddefconfig},
/*
* oldnoconfig is an alias of olddefconfig, because people already
* are dependent on its behavior(sets new symbols to their default
* value but not 'n') with the counter-intuitive name.
*/
{"oldnoconfig", no_argument, NULL, olddefconfig},
{NULL, 0, NULL, 0}
};
@ -480,7 +474,6 @@ static void conf_usage(const char *progname)
printf(" --syncconfig Similar to oldconfig but generates configuration in\n"
" include/{generated/,config/}\n");
printf(" --olddefconfig Same as oldconfig but sets new symbols to their default value\n");
printf(" --oldnoconfig An alias of olddefconfig\n");
printf(" --defconfig <file> New config with default defined in <file>\n");
printf(" --savedefconfig <file> Save the minimal current configuration to <file>\n");
printf(" --allnoconfig New config where all options are answered with no\n");

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@ -33,12 +33,15 @@ usage() {
echo " -n use allnoconfig instead of alldefconfig"
echo " -r list redundant entries when merging fragments"
echo " -O dir to put generated output files. Consider setting \$KCONFIG_CONFIG instead."
echo
echo "Used prefix: '$CONFIG_PREFIX'. You can redefine it with \$CONFIG_ environment variable."
}
RUNMAKE=true
ALLTARGET=alldefconfig
WARNREDUN=false
OUTPUT=.
CONFIG_PREFIX=${CONFIG_-CONFIG_}
while true; do
case $1 in
@ -99,7 +102,9 @@ if [ ! -r "$INITFILE" ]; then
fi
MERGE_LIST=$*
SED_CONFIG_EXP="s/^\(# \)\{0,1\}\(CONFIG_[a-zA-Z0-9_]*\)[= ].*/\2/p"
SED_CONFIG_EXP1="s/^\(${CONFIG_PREFIX}[a-zA-Z0-9_]*\)=.*/\1/p"
SED_CONFIG_EXP2="s/^# \(${CONFIG_PREFIX}[a-zA-Z0-9_]*\) is not set$/\1/p"
TMP_FILE=$(mktemp ./.tmp.config.XXXXXXXXXX)
echo "Using $INITFILE as base"
@ -112,7 +117,7 @@ for MERGE_FILE in $MERGE_LIST ; do
echo "The merge file '$MERGE_FILE' does not exist. Exit." >&2
exit 1
fi
CFG_LIST=$(sed -n "$SED_CONFIG_EXP" $MERGE_FILE)
CFG_LIST=$(sed -n -e "$SED_CONFIG_EXP1" -e "$SED_CONFIG_EXP2" $MERGE_FILE)
for CFG in $CFG_LIST ; do
grep -q -w $CFG $TMP_FILE || continue
@ -155,7 +160,7 @@ make KCONFIG_ALLCONFIG=$TMP_FILE $OUTPUT_ARG $ALLTARGET
# Check all specified config values took (might have missed-dependency issues)
for CFG in $(sed -n "$SED_CONFIG_EXP" $TMP_FILE); do
for CFG in $(sed -n -e "$SED_CONFIG_EXP1" -e "$SED_CONFIG_EXP2" $TMP_FILE); do
REQUESTED_VAL=$(grep -w -e "$CFG" $TMP_FILE)
ACTUAL_VAL=$(grep -w -e "$CFG" "$KCONFIG_CONFIG")

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@ -1,35 +1,25 @@
#!/bin/sh
# SPDX-License-Identifier: GPL-2.0
# Generates a small Makefile used in the root of the output
# directory, to allow make to be started from there.
# The Makefile also allow for more convinient build of external modules
# Usage
# $1 - Kernel src directory
# $2 - Output directory
# $3 - version
# $4 - patchlevel
test ! -r $2/Makefile -o -O $2/Makefile || exit 0
# Only overwrite automatically generated Makefiles
# (so we do not overwrite kernel Makefile)
if test -e $2/Makefile && ! grep -q Automatically $2/Makefile
if test -e Makefile && ! grep -q Automatically Makefile
then
exit 0
fi
if [ "${quiet}" != "silent_" ]; then
echo " GEN $2/Makefile"
echo " GEN Makefile"
fi
cat << EOF > $2/Makefile
cat << EOF > Makefile
# Automatically generated by $0: don't edit
VERSION = $3
PATCHLEVEL = $4
lastword = \$(word \$(words \$(1)),\$(1))
makedir := \$(dir \$(call lastword,\$(MAKEFILE_LIST)))
ifeq ("\$(origin V)", "command line")
VERBOSE := \$(V)
endif
@ -37,15 +27,12 @@ ifneq (\$(VERBOSE),1)
Q := @
endif
MAKEARGS := -C $1
MAKEARGS += O=\$(if \$(patsubst /%,,\$(makedir)),\$(CURDIR)/)\$(patsubst %/,%,\$(makedir))
MAKEFLAGS += --no-print-directory
.PHONY: __sub-make \$(MAKECMDGOALS)
__sub-make:
\$(Q)\$(MAKE) \$(MAKEARGS) \$(MAKECMDGOALS)
\$(Q)\$(MAKE) -C $1 O=\$(CURDIR) \$(MAKECMDGOALS)
\$(filter-out __sub-make, \$(MAKECMDGOALS)): __sub-make
@: