initial buildroot for linux 5.15

support/dependencies/check-host-asciidoc.sh

@@ -0,0 +1,36 @@
+#!/bin/sh
+
+candidate="$1" #ignored
+
+asciidoc=`which asciidoc`
+if [ ! -x "$asciidoc" ]; then
+	# echo nothing: no suitable asciidoc found
+	exit 1
+fi
+
+# Output of 'asciidoc --version' examples:
+# asciidoc 8.6.7
+version=`$asciidoc --version | cut -d\  -f2`
+major=`echo "$version" | cut -d. -f1`
+minor=`echo "$version" | cut -d. -f2`
+bugfix=`echo "$version" | cut -d. -f3`
+
+# To generate the manual, we need asciidoc >= 8.6.3
+major_min=8
+minor_min=6
+bugfix_min=3
+if [ $major -gt $major_min ]; then
+	echo $asciidoc
+else
+	if [ $major -eq $major_min -a $minor -ge $minor_min ]; then
+		echo $asciidoc
+	else
+		if [ $major -eq $major_min -a $minor -eq $minor_min \
+			-a $bugfix -ge $bugfix_min ]; then
+			echo $asciidoc
+		else
+			# echo nothing: no suitable asciidoc found
+			exit 1
+		fi
+	fi
+fi

support/dependencies/check-host-bison-flex.mk

@@ -0,0 +1,14 @@
+# If the system lacks bison or flex, add
+# dependencies to suitable host packages
+#
+# BR2_{BISON,FLES}_HOST_DEPENDENCY should only be used to build code
+# that runs on host, e.g. Kconfig. To build code for target use plain
+# host-{bison,flex}.
+
+ifeq ($(shell which bison 2>/dev/null),)
+BR2_BISON_HOST_DEPENDENCY = host-bison
+endif
+
+ifeq ($(shell which flex 2>/dev/null),)
+BR2_FLEX_HOST_DEPENDENCY = host-flex
+endif

support/dependencies/check-host-cmake.mk

@@ -0,0 +1,14 @@
+# Set this to either 3.16 or higher, depending on the highest minimum
+# version required by any of the packages bundled in Buildroot. If a
+# package is bumped or a new one added, and it requires a higher
+# version, our cmake infra will catch it and build its own.
+#
+BR2_CMAKE_VERSION_MIN = 3.16
+
+BR2_CMAKE_CANDIDATES ?= cmake cmake3
+BR2_CMAKE ?= $(call suitable-host-package,cmake,\
+	$(BR2_CMAKE_VERSION_MIN) $(BR2_CMAKE_CANDIDATES))
+ifeq ($(BR2_CMAKE),)
+BR2_CMAKE = $(HOST_DIR)/bin/cmake
+BR2_CMAKE_HOST_DEPENDENCY = host-cmake
+endif

support/dependencies/check-host-cmake.sh

@@ -0,0 +1,45 @@
+#!/bin/sh
+
+# prevent shift error
+[ $# -lt 2 ] && exit 1
+
+major_min="${1%.*}"
+minor_min="${1#*.}"
+
+shift
+
+for candidate; do
+
+    # Try to locate the candidate. Discard it if not located.
+    cmake=`which "${candidate}" 2>/dev/null`
+    [ -n "${cmake}" ] || continue
+
+    # Extract version X.Y from versions in the form X.Y or X.Y.Z
+    # with X, Y and Z numbers with one or more digits each, e.g.
+    #   3.2     -> 3.2
+    #   3.2.3   -> 3.2
+    #   3.2.42  -> 3.2
+    #   3.10    -> 3.10
+    #   3.10.4  -> 3.10
+    #   3.10.42 -> 3.10
+    # Discard the candidate if no version can be obtained
+    version="$(${cmake} --version \
+               |sed -r -e '/.* ([[:digit:]]+\.[[:digit:]]+).*$/!d;' \
+                       -e 's//\1/'
+              )"
+    [ -n "${version}" ] || continue
+
+    major="${version%.*}"
+    minor="${version#*.}"
+
+    if [ ${major} -gt ${major_min} ]; then
+        echo "${cmake}"
+        exit
+    elif [ ${major} -eq ${major_min} -a ${minor} -ge ${minor_min} ]; then
+        echo "${cmake}"
+        exit
+    fi
+done
+
+# echo nothing: no suitable cmake found
+exit 1

support/dependencies/check-host-coreutils.mk

@@ -0,0 +1,6 @@
+# Check whether the host's coreutils are up to date enough
+# to provide 'ln --relative' and 'realpath'.
+
+ifeq (,$(call suitable-host-package,coreutils))
+BR2_COREUTILS_HOST_DEPENDENCY = host-coreutils
+endif

support/dependencies/check-host-coreutils.sh

@@ -0,0 +1,12 @@
+#!/bin/sh
+
+# Exit on the first error
+set -e
+
+# Does ln supports the --relative/-r option?
+ln --relative --help >/dev/null 2>&1
+
+# Does realpath exist?
+realpath --help >/dev/null 2>&1
+
+echo OK

support/dependencies/check-host-gzip.mk

@@ -0,0 +1,3 @@
+ifeq (,$(call suitable-host-package,gzip))
+BR2_GZIP_HOST_DEPENDENCY = host-gzip
+endif

support/dependencies/check-host-gzip.sh

@@ -0,0 +1,21 @@
+#!/bin/sh
+
+candidate="$1" # ignored
+
+gzip="$(which gzip)"
+if [ ! -x "${gzip}" ]; then
+    # echo nothing: no suitable gzip found
+    exit 1
+fi
+
+# gzip displays its version string on stdout
+# pigz displays its version string on stderr
+version="$("${gzip}" --version 2>&1)"
+case "${version}" in
+  (*pigz*)
+    # echo nothing: no suitable gzip found
+    exit 1
+    ;;
+esac
+
+printf "%s" "${gzip}"

support/dependencies/check-host-lzip.mk

@@ -0,0 +1,4 @@
+ifeq (,$(call suitable-host-package,lzip,$(LZCAT)))
+BR2_LZIP_HOST_DEPENDENCY = host-lzip
+LZCAT = $(HOST_DIR)/bin/lzip -d -c
+endif

support/dependencies/check-host-lzip.sh

@@ -0,0 +1,14 @@
+#!/bin/sh
+
+candidate="$1"
+
+lzip=`which $candidate 2>/dev/null`
+if [ ! -x "$lzip" ]; then
+	lzip=`which lzip 2>/dev/null`
+	if [ ! -x "$lzip" ]; then
+		# echo nothing: no suitable lzip found
+		exit 1
+	fi
+fi
+
+echo $lzip

support/dependencies/check-host-make.mk

@@ -0,0 +1,21 @@
+# Since version 2.28, glibc requires GNU Make >= 4.0
+# https://www.sourceware.org/ml/libc-alpha/2018-08/msg00003.html
+#
+# Set this to either 4.0 or higher, depending on the highest minimum
+# version required by any of the packages bundled in Buildroot. If a
+# package is bumped or a new one added, and it requires a higher
+# version, our package infra will catch it and whine.
+#
+BR2_MAKE_VERSION_MIN = 4.0
+
+BR2_MAKE ?= $(call suitable-host-package,make,\
+	$(BR2_MAKE_VERSION_MIN) $(MAKE))
+
+ifeq ($(BR2_MAKE),)
+BR2_MAKE = $(HOST_DIR)/bin/host-make -j$(PARALLEL_JOBS)
+BR2_MAKE1 = $(HOST_DIR)/bin/host-make -j1
+BR2_MAKE_HOST_DEPENDENCY = host-make
+else
+BR2_MAKE = $(MAKE)
+BR2_MAKE1 = $(MAKE1)
+endif

support/dependencies/check-host-make.sh

@@ -0,0 +1,37 @@
+#!/bin/sh
+
+# prevent shift error
+[ $# -lt 2 ] && exit 1
+
+major_min="${1%.*}"
+minor_min="${1#*.}"
+
+shift
+
+# The host make program is already checked by dependencies.sh but we
+# want to check the version number even if Buildroot is able to use
+# GNU make >= 3.81 but some packages may require a more recent version.
+make="$1"
+
+# Output of 'make --version' examples:
+# GNU Make 4.2.1
+# GNU Make 4.0
+# GNU Make 3.81
+version=`$make --version 2>&1 | sed -e 's/^.* \([0-9\.]\)/\1/g' -e 's/[-\
+].*//g' -e '1q'`
+
+major=`echo "$version" | cut -d. -f1`
+minor=`echo "$version" | cut -d. -f2`
+
+if [ $major -lt $major_min ]; then
+	# echo nothing: no suitable make found
+	exit 1
+fi
+
+if [ $major -eq $major_min -a $minor -lt $minor_min ]; then
+	# echo nothing: no suitable make found
+	exit 1
+fi
+
+# valid
+echo $make

support/dependencies/check-host-python3.mk

@@ -0,0 +1,8 @@
+# Since version 2.29, glibc requires python 3.4 or later to build the GNU C Library.
+# https://www.sourceware.org/ml/libc-alpha/2019-01/msg00723.html
+
+BR2_PYTHON3_VERSION_MIN = 3.4
+
+ifeq (,$(call suitable-host-package,python3,$(BR2_PYTHON3_VERSION_MIN) python3 python))
+BR2_PYTHON3_HOST_DEPENDENCY = host-python3
+endif

support/dependencies/check-host-python3.sh

@@ -0,0 +1,31 @@
+#!/bin/sh
+
+# prevent shift error
+[ $# -lt 2 ] && exit 1
+
+version_min="$(echo ${1} | awk '{ split($1, v, "."); print v[1] v[2] }')"
+
+shift
+
+# The host python interpreter is already checked by dependencies.sh but
+# it only check if the version is at least 2.7.
+# We want to check the version number of the python3 interpreter even
+# if Buildroot is able to use any version but some packages may require
+# a more recent version.
+
+for candidate in "${@}" ; do
+	python3=`which $candidate 2>/dev/null`
+	if [ ! -x "$python3" ]; then
+		continue
+	fi
+	version=`$python3 -V 2>&1 | awk '{ split($2, v, "."); print v[1] v[2] }'`
+
+	if [ $version -lt $version_min ]; then
+		# no suitable python3 found
+		continue
+	fi
+
+	# suitable python3 found
+	echo $python3
+	break
+done

support/dependencies/check-host-tar.mk

@@ -0,0 +1,6 @@
+TAR ?= tar
+
+ifeq (,$(call suitable-host-package,tar,$(TAR)))
+TAR = $(HOST_DIR)/bin/tar
+BR2_TAR_HOST_DEPENDENCY = host-tar
+endif

support/dependencies/check-host-tar.sh

@@ -0,0 +1,47 @@
+#!/bin/sh
+
+candidate="$1"
+
+tar=`which $candidate`
+if [ ! -x "$tar" ]; then
+	tar=`which tar`
+	if [ ! -x "$tar" ]; then
+		# echo nothing: no suitable tar found
+		exit 1
+	fi
+fi
+
+# Output of 'tar --version' examples:
+# tar (GNU tar) 1.15.1
+# tar (GNU tar) 1.25
+# bsdtar 2.8.3 - libarchive 2.8.3
+version=`$tar --version | head -n 1 | sed 's/^.*\s\([0-9]\+\.\S\+\).*$/\1/'`
+major=`echo "$version" | cut -d. -f1`
+minor=`echo "$version" | cut -d. -f2`
+bugfix=`echo "$version" | cut -d. -f3`
+version_bsd=`$tar --version | grep 'bsdtar'`
+
+# BSD tar does not have all the command-line options
+if [ -n "${version_bsd}" ] ; then
+    # echo nothing: no suitable tar found
+    exit 1
+fi
+
+# Minimal version = 1.27 (previous versions do not correctly unpack archives
+# containing hard-links if the --strip-components option is used or create
+# different gnu long link headers for path elements > 100 characters).
+major_min=1
+minor_min=27
+
+if [ $major -lt $major_min ]; then
+	# echo nothing: no suitable tar found
+	exit 1
+fi
+
+if [ $major -eq $major_min -a $minor -lt $minor_min ]; then
+	# echo nothing: no suitable tar found
+	exit 1
+fi
+
+# valid
+echo $tar

support/dependencies/check-host-xzcat.mk

@@ -0,0 +1,7 @@
+# XZCAT is taken from BR2_XZCAT (defaults to 'xzcat') (see Makefile)
+# If it is not present, build our own host-xzcat
+
+ifeq (,$(call suitable-host-package,xzcat,$(XZCAT)))
+BR2_XZCAT_HOST_DEPENDENCY = host-xz
+XZCAT = $(HOST_DIR)/bin/xzcat
+endif

support/dependencies/check-host-xzcat.sh

@@ -0,0 +1,14 @@
+#!/bin/sh
+
+candidate="$1"
+
+xzcat=`which $candidate 2>/dev/null`
+if [ ! -x "$xzcat" ]; then
+	xzcat=`which xzcat 2>/dev/null`
+	if [ ! -x "$xzcat" ]; then
+		# echo nothing: no suitable xzcat found
+		exit 1
+	fi
+fi
+
+echo $xzcat

support/dependencies/dependencies.mk

@@ -0,0 +1,35 @@
+################################################################################
+#
+# Check buildroot dependencies and bail out if the user's
+# system is judged to be lacking....
+#
+################################################################################
+
+ifeq ($(BR2_FORCE_HOST_BUILD),y)
+# ignore all available host packages
+define suitable-host-package
+endef
+else
+# suitable-host-pkg: calls check-host-$(1).sh shell script. Parameter (2)
+# can be the candidate to be checked. If not present, the check-host-$(1).sh
+# script should use 'which' to find a candidate. The script should return
+# the path to the suitable host tool, or nothing if no suitable tool was found.
+define suitable-host-package
+$(if $(1),$(shell support/dependencies/check-host-$(1).sh $(2)))
+endef
+endif
+# host utilities needs host-tar to extract the source code tarballs, so
+# ensure check-host-tar.mk is included before the rest
+include support/dependencies/check-host-tar.mk
+-include $(sort $(filter-out %-tar.mk,$(wildcard support/dependencies/check-host-*.mk)))
+
+dependencies:
+	@MAKE="$(MAKE)" DL_TOOLS="$(sort $(DL_TOOLS_DEPENDENCIES))" \
+		$(TOPDIR)/support/dependencies/dependencies.sh
+
+################################################################################
+#
+# Toplevel Makefile options
+#
+################################################################################
+.PHONY: dependencies

support/dependencies/dependencies.sh

@@ -0,0 +1,306 @@
+#!/bin/sh
+# vi: set sw=4 ts=4:
+
+export LC_ALL=C
+TAB="$(printf '\t')"
+NL="
+"
+
+# Verify that grep works
+echo "WORKS" | grep "WORKS" >/dev/null 2>&1
+if test $? != 0 ; then
+	echo
+	echo "grep doesn't work"
+	exit 1
+fi
+
+# Sanity check for CWD in LD_LIBRARY_PATH
+case ":${LD_LIBRARY_PATH:-unset}:" in
+(*::*|*:.:*)
+	echo
+	echo "You seem to have the current working directory in your"
+	echo "LD_LIBRARY_PATH environment variable. This doesn't work."
+	exit 1
+	;;
+esac
+
+# Sanity check for CWD in PATH. Having the current working directory
+# in the PATH makes various packages (e.g. toolchain, coreutils...)
+# build process break.
+# PATH should not contain a newline, otherwise it fails in spectacular
+# ways as soon as PATH is referenced in a package rule
+# An empty PATH is technically possible, but in practice we would not
+# even arrive here if that was the case.
+case ":${PATH:-unset}:" in
+(*::*|*:.:*)
+	echo
+	echo "You seem to have the current working directory in your"
+	echo "PATH environment variable. This doesn't work."
+	exit 1
+	;;
+(*" "*|*"${TAB}"*|*"${NL}"*)
+	printf "\n"
+	printf "Your PATH contains spaces, TABs, and/or newline (\\\n) characters.\n"
+	printf "This doesn't work. Fix you PATH.\n"
+	exit 1
+	;;
+esac
+
+if test -n "$PERL_MM_OPT" ; then
+	echo
+	echo "You have PERL_MM_OPT defined because Perl local::lib"
+	echo "is installed on your system. Please unset this variable"
+	echo "before starting Buildroot, otherwise the compilation of"
+	echo "Perl related packages will fail"
+	exit 1
+fi
+
+check_prog_host()
+{
+	prog="$1"
+	if ! which $prog > /dev/null ; then
+		echo >&2
+		echo "You must install '$prog' on your build machine" >&2
+		exit 1
+	fi
+}
+
+# Verify that which is installed
+check_prog_host "which"
+# Verify that sed is installed
+check_prog_host "sed"
+
+# 'file' must be present and must be exactly /usr/bin/file,
+# otherwise libtool fails in incomprehensible ways.
+check_prog_host "/usr/bin/file"
+
+# Check make
+MAKE=$(which make 2> /dev/null)
+if [ -z "$MAKE" ] ; then
+	echo
+	echo "You must install 'make' on your build machine";
+	exit 1;
+fi;
+MAKE_VERSION=$($MAKE --version 2>&1 | sed -e 's/^.* \([0-9\.]\)/\1/g' -e 's/[-\ ].*//g' -e '1q')
+if [ -z "$MAKE_VERSION" ] ; then
+	echo
+	echo "You must install 'make' on your build machine";
+	exit 1;
+fi;
+MAKE_MAJOR=$(echo $MAKE_VERSION | sed -e "s/\..*//g")
+MAKE_MINOR=$(echo $MAKE_VERSION | sed -e "s/^$MAKE_MAJOR\.//g" -e "s/\..*//g" -e "s/[a-zA-Z].*//g")
+if [ $MAKE_MAJOR -lt 3 ] || [ $MAKE_MAJOR -eq 3 -a $MAKE_MINOR -lt 81 ] ; then
+	echo
+	echo "You have make '$MAKE_VERSION' installed.  GNU make >=3.81 is required"
+	exit 1;
+fi;
+
+# Check host gcc
+COMPILER=$(which $HOSTCC_NOCCACHE 2> /dev/null)
+if [ -z "$COMPILER" ] ; then
+	COMPILER=$(which cc 2> /dev/null)
+fi;
+if [ -z "$COMPILER" ] ; then
+	echo
+	echo "You must install 'gcc' on your build machine";
+	exit 1;
+fi;
+
+COMPILER_VERSION=$($COMPILER -v 2>&1 | sed -n '/^gcc version/p' |
+	sed -e 's/^gcc version \([0-9\.]\)/\1/g' -e 's/[-\ ].*//g' -e '1q')
+if [ -z "$COMPILER_VERSION" ] ; then
+	echo
+	echo "You must install 'gcc' on your build machine";
+	exit 1;
+fi;
+COMPILER_MAJOR=$(echo $COMPILER_VERSION | sed -e "s/\..*//g")
+COMPILER_MINOR=$(echo $COMPILER_VERSION | sed -e "s/^$COMPILER_MAJOR\.//g" -e "s/\..*//g")
+if [ $COMPILER_MAJOR -lt 4 -o $COMPILER_MAJOR -eq 4 -a $COMPILER_MINOR -lt 8 ] ; then
+	echo
+	echo "You have gcc '$COMPILER_VERSION' installed.  gcc >= 4.8 is required"
+	exit 1;
+fi;
+
+# check for host CXX
+CXXCOMPILER=$(which $HOSTCXX_NOCCACHE 2> /dev/null)
+if [ -z "$CXXCOMPILER" ] ; then
+	CXXCOMPILER=$(which c++ 2> /dev/null)
+fi
+
+if [ -z "$CXXCOMPILER" ] ; then
+	echo
+	echo "You may have to install 'g++' on your build machine"
+fi
+if [ ! -z "$CXXCOMPILER" ] ; then
+	CXXCOMPILER_VERSION=$($CXXCOMPILER -v 2>&1 | sed -n '/^gcc version/p' |
+		sed -e 's/^gcc version \([0-9\.]\)/\1/g' -e 's/[-\ ].*//g' -e '1q')
+	if [ -z "$CXXCOMPILER_VERSION" ] ; then
+		echo
+		echo "You may have to install 'g++' on your build machine"
+	fi
+fi
+
+if [ -n "$CXXCOMPILER_VERSION" ] ; then
+	CXXCOMPILER_MAJOR=$(echo $CXXCOMPILER_VERSION | sed -e "s/\..*//g")
+	CXXCOMPILER_MINOR=$(echo $CXXCOMPILER_VERSION | sed -e "s/^$CXXCOMPILER_MAJOR\.//g" -e "s/\..*//g")
+	if [ $CXXCOMPILER_MAJOR -lt 4 -o $CXXCOMPILER_MAJOR -eq 4 -a $CXXCOMPILER_MINOR -lt 8 ] ; then
+		echo
+		echo "You have g++ '$CXXCOMPILER_VERSION' installed.  g++ >= 4.8 is required"
+		exit 1
+	fi
+fi
+
+# Check bash
+# We only check bash is available, setting SHELL appropriately is done
+# in the top-level Makefile, and we mimick the same sequence here
+if   [ -n "${BASH}" ]; then :
+elif [ -x /bin/bash ]; then :
+elif [ -z "$( sh -c 'echo $BASH' )" ]; then
+	echo
+	echo "You must install 'bash' on your build machine"
+	exit 1
+fi
+
+# Check that a few mandatory programs are installed
+missing_progs="no"
+for prog in perl tar wget cpio unzip rsync bc ${DL_TOOLS} ; do
+	if ! which $prog > /dev/null ; then
+		echo "You must install '$prog' on your build machine";
+		missing_progs="yes"
+		if test $prog = "svn" ; then
+			echo "  svn is usually part of the subversion package in your distribution"
+		elif test $prog = "hg" ; then
+			echo "  hg is usually part of the mercurial package in your distribution"
+		elif test $prog = "zcat" ; then
+			echo "  zcat is usually part of the gzip package in your distribution"
+		elif test $prog = "bzcat" ; then
+			echo "  bzcat is usually part of the bzip2 package in your distribution"
+		fi
+	fi
+done
+
+if test "${missing_progs}" = "yes" ; then
+	exit 1
+fi
+
+PATCH_VERSION="$(patch -v 2>/dev/null | sed -n 's/^GNU patch \(.*\)/\1/p')"
+if [ -z "${PATCH_VERSION}" ] ; then
+	echo
+	echo "You must install GNU patch"
+	exit 1
+fi
+PATCH_MAJOR="$(echo "${PATCH_VERSION}" | cut -d . -f 1)"
+PATCH_MINOR="$(echo "${PATCH_VERSION}" | cut -d . -f 2)"
+if [ "${PATCH_MAJOR}" -lt 2 ] || [ "${PATCH_MAJOR}" -eq 2 -a "${PATCH_MINOR}" -lt 7 ] ; then
+	echo
+	echo "You have GNU patch '${PATCH_VERSION}' installed.  GNU patch >= 2.7 is required"
+	exit 1;
+fi
+
+if grep ^BR2_NEEDS_HOST_UTF8_LOCALE=y $BR2_CONFIG > /dev/null; then
+	if ! which locale > /dev/null ; then
+		echo
+		echo "You need locale support on your build machine to build a toolchain supporting locales"
+		exit 1 ;
+	fi
+	if ! locale -a | grep -q -i -E 'utf-?8$' ; then
+		echo
+		echo "You need at least one UTF8 locale to build a toolchain supporting locales"
+		exit 1 ;
+	fi
+fi
+
+if grep -q ^BR2_NEEDS_HOST_JAVA=y $BR2_CONFIG ; then
+	check_prog_host "java"
+	JAVA_GCJ=$(java -version 2>&1 | grep gcj)
+	if [ ! -z "$JAVA_GCJ" ] ; then
+		echo
+		echo "$JAVA_GCJ is not sufficient to compile your package selection."
+		echo "Please install an OpenJDK/IcedTea/Oracle Java."
+		exit 1 ;
+	fi
+fi
+
+if grep -q ^BR2_HOSTARCH_NEEDS_IA32_LIBS=y $BR2_CONFIG ; then
+	if test ! -f /lib/ld-linux.so.2 ; then
+		echo
+		echo "Your Buildroot configuration uses pre-built tools for the x86 architecture,"
+		echo "but your build machine uses the x86-64 architecture without the 32 bits compatibility"
+		echo "library."
+		echo "If you're running a Debian/Ubuntu distribution, install the libc6-i386,"
+		echo "lib32stdc++6, and lib32z1 packages (or alternatively libc6:i386,"
+		echo "libstdc++6:i386, and zlib1g:i386)."
+		echo "If you're running a RedHat/Fedora distribution, install the glibc.i686 and"
+		echo "zlib.i686 packages."
+		echo "If you're running an ArchLinux distribution, install lib32-glibc."
+		echo "For other distributions, refer to the documentation on how to install the 32 bits"
+		echo "compatibility libraries."
+		exit 1
+	fi
+fi
+
+if grep -q ^BR2_HOSTARCH_NEEDS_IA32_COMPILER=y $BR2_CONFIG ; then
+	if ! echo "int main(void) {}" | gcc -m32 -x c - -o /dev/null 2>/dev/null; then
+		echo
+		echo "Your Buildroot configuration needs a compiler capable of building 32 bits binaries."
+		echo "If you're running a Debian/Ubuntu distribution, install the gcc-multilib package."
+		echo "For other distributions, refer to their documentation."
+		exit 1
+	fi
+
+	if ! echo "int main(void) {}" | g++ -m32 -x c++ - -o /dev/null 2>/dev/null; then
+		echo
+		echo "Your Buildroot configuration needs a compiler capable of building 32 bits binaries."
+		echo "If you're running a Debian/Ubuntu distribution, install the g++-multilib package."
+		echo "For other distributions, refer to their documentation."
+		exit 1
+	fi
+fi
+
+if grep ^BR2_NEEDS_HOST_GCC_PLUGIN_SUPPORT=y $BR2_CONFIG ; then
+	if ! echo "#include <gcc-plugin.h>" | $HOSTCXX_NOCCACHE -I$($HOSTCXX_NOCCACHE -print-file-name=plugin)/include -x c++ -c - -o /dev/null ; then
+		echo
+		echo "Your Buildroot configuration needs a host compiler capable of building gcc plugins."
+		echo "If you're running a Debian/Ubuntu distribution, install gcc-X-plugin-dev package."
+		echo "For other distributions, refer to their documentation."
+		exit 1 ;
+	fi
+fi
+
+# Check that the Perl installation is complete enough for Buildroot.
+required_perl_modules="Data::Dumper" # Needed to build host-autoconf
+required_perl_modules="$required_perl_modules ExtUtils::MakeMaker" # Used by host-libxml-parser-perl
+required_perl_modules="$required_perl_modules Thread::Queue" # Used by host-automake
+
+if grep -q ^BR2_PACKAGE_MPV=y $BR2_CONFIG ; then
+    required_perl_modules="$required_perl_modules Math::BigInt"
+    required_perl_modules="$required_perl_modules Math::BigRat"
+fi
+
+if grep -q ^BR2_PACKAGE_WHOIS=y $BR2_CONFIG ; then
+    required_perl_modules="$required_perl_modules autodie"
+fi
+
+if grep -q -E '^BR2_PACKAGE_(WEBKITGTK|WPEWEBKIT)=y' $BR2_CONFIG ; then
+    required_perl_modules="${required_perl_modules} JSON::PP"
+fi
+
+# This variable will keep the modules that are missing in your system.
+missing_perl_modules=""
+
+for pm in $required_perl_modules ; do
+	if ! perl  -e "require $pm" > /dev/null 2>&1 ; then
+		missing_perl_modules="$missing_perl_modules $pm"
+	fi
+done
+
+if [ -n "$missing_perl_modules" ] ; then
+	echo "Your Perl installation is not complete enough; at least the following"
+	echo "modules are missing:"
+	echo
+	for pm in $missing_perl_modules ; do
+		printf "\t $pm\n"
+	done
+	echo
+	exit 1
+fi