scripts/make.sh - platform/external/toybox - Git at Google

 #!/bin/bash

 # Grab default values for $CFLAGS and such.

 set -o pipefail
 source scripts/portability.sh

 # Default to running one more parallel cc instance than we have processors
 : ${CPUS:=$(($(nproc 2>/dev/null || sysctl -n hw.ncpu 2>/dev/null)+1))}

 # Respond to V= by echoing command lines as well as running them
 DOTPROG=
 do_loudly()
 {
   [ ! -z "$V" ] && echo "$@" || echo -n "$DOTPROG"
   "$@"
 }

 # Is anything under directory $2 newer than file $1
 isnewer()
 {
   CHECK="$1"
   shift
   [ ! -z "$(find "$@" -newer "$CHECK" 2>/dev/null || echo yes)" ]
 }

 echo "Generate headers from toys/*/*.c..."

 mkdir -p "${UNSTRIPPED:=$GENDIR/unstripped}"

 if isnewer "$GENDIR"/Config.in toys || isnewer "$GENDIR"/Config.in Config.in
 then
   echo "Extract configuration information from toys/*.c files..."
   scripts/genconfig.sh
 fi

 # Create a list of all the commands toybox can provide. Note that the first
 # entry is out of order on purpose (the toybox multiplexer command must be the
 # first element of the array). The rest must be sorted in alphabetical order
 # for fast binary search.

 if isnewer "$GENDIR"/newtoys.h toys
 then
   echo -n "$GENDIR/newtoys.h "

   echo "USE_TOYBOX(NEWTOY(toybox, NULL, TOYFLAG_STAYROOT))" > "$GENDIR"/newtoys.h
   $SED -n -e 's/^USE_[A-Z0-9_]*(/&/p' toys/*/*.c \
 	| $SED 's/\(.*TOY(\)\([^,]*\),\(.*\)/\2 \1\2,\3/' | sort -s -k 1,1 \
 	| $SED 's/[^ ]* //'  >> "$GENDIR"/newtoys.h
   [ $? -ne 0 ] && exit 1
 fi

 [ ! -z "$V" ] && echo "Which C files to build..."

 # Extract a list of toys/*/*.c files to compile from the data in $KCONFIG_CONFIG
 # (First command names, then filenames with relevant {NEW,OLD}TOY() macro.)

 [ -d ".git" ] && GITHASH="-DTOYBOX_VERSION=\"$(git describe --tags --abbrev=12 2>/dev/null)\""
 TOYFILES="$($SED -n 's/^CONFIG_\([^=]*\)=.*/\1/p' "$KCONFIG_CONFIG" | xargs | tr ' [A-Z]' '|[a-z]')"
 TOYFILES="main.c $(egrep -l "TOY[(]($TOYFILES)[ ,]" toys/*/*.c | xargs)"
 BUILD="$(echo ${CROSS_COMPILE}${CC} $CFLAGS -I . $OPTIMIZE $GITHASH)"

 if [ "${TOYFILES/pending//}" != "$TOYFILES" ]
 then
   echo -e "\n\033[1;31mwarning: using unfinished code from toys/pending\033[0m"
 fi

 genbuildsh()
 {
   # Write a canned build line for use on crippled build machines.

   echo -e "#!/bin/sh\n\nPATH='$PATH'\nBUILD='$BUILD'\nLINK='$LINK'\n"
   echo -e "\$BUILD lib/*.c $TOYFILES \$LINK -o $OUTNAME"
 }

 if ! cmp -s <(genbuildsh 2>/dev/null | head -n 4 ; echo LINK="'"$LDOPTIMIZE $LDFLAGS) \
           <(head -n 5 "$GENDIR"/build.sh 2>/dev/null | $SED '5s/ -o .*//')
 then
   echo -n "Library probe"

   # --as-needed removes libraries we don't use any symbols out of, but the
   # compiler has no way to ignore a library that doesn't exist, so detect
   # and skip nonexistent libraries for it.

   > "$GENDIR"/optlibs.dat
   for i in util crypt m resolv selinux smack attr crypto z log iconv tls ssl
   do
     echo "int main(int argc, char *argv[]) {return 0;}" | \
     ${CROSS_COMPILE}${CC} $CFLAGS $LDFLAGS -xc - -o "$GENDIR"/libprobe -l$i > /dev/null 2>/dev/null &&
     echo -l$i >> "$GENDIR"/optlibs.dat
     echo -n .
   done
   rm -f "$GENDIR"/libprobe
   echo
 fi

 # LINK needs optlibs.dat, above

 LINK="$(echo $LDOPTIMIZE $LDFLAGS $(cat "$GENDIR"/optlibs.dat))"
 genbuildsh > "$GENDIR"/build.sh && chmod +x "$GENDIR"/build.sh || exit 1

 #TODO: "make $SED && make" doesn't regenerate config.h because diff .config
 if true #isnewer "$GENDIR"/config.h "$KCONFIG_CONFIG"
 then
   echo "Make $GENDIR/config.h from $KCONFIG_CONFIG."

   # This long and roundabout sed invocation is to make old versions of sed
   # happy. New ones have '\n' so can replace one line with two without all
   # the branches and tedious mucking about with hyperspace.
   # TODO: clean this up to use modern stuff.

   $SED -n \
     -e 's/^# CONFIG_\(.*\) is not set.*/\1/' \
     -e 't notset' \
     -e 's/^CONFIG_\(.*\)=y.*/\1/' \
     -e 't isset' \
     -e 's/^CONFIG_\([^=]*\)=\(.*\)/#define CFG_\1 \2/p' \
     -e 'd' \
     -e ':notset' \
     -e 'h' \
     -e 's/.*/#define CFG_& 0/p' \
     -e 'g' \
     -e 's/.*/#define USE_&(...)/p' \
     -e 'd' \
     -e ':isset' \
     -e 'h' \
     -e 's/.*/#define CFG_& 1/p' \
     -e 'g' \
     -e 's/.*/#define USE_&(...) __VA_ARGS__/p' \
     $KCONFIG_CONFIG > "$GENDIR"/config.h || exit 1
 fi

 if [ ! -f "$GENDIR"/mkflags ] || [ "$GENDIR"/mkflags -ot scripts/mkflags.c ]
 then
   do_loudly $HOSTCC scripts/mkflags.c -o "$UNSTRIPPED"/mkflags || exit 1
 fi

 # Process config.h and newtoys.h to generate FLAG_x macros. Note we must
 # always #define the relevant macro, even when it's disabled, because we
 # allow multiple NEWTOY() in the same C file. (When disabled the FLAG is 0,
 # so flags&0 becomes a constant 0 allowing dead code elimination.)

 if isnewer "$GENDIR"/flags.h toys "$KCONFIG_CONFIG"
 then
   echo -n "$GENDIR/flags.h "

   # Parse files through C preprocessor twice, once to get flags for current
   # .config and once to get flags for allyesconfig
   for I in A B
   do
     (
     # define macros and select header files with option string data

     echo "#define NEWTOY(aa,bb,cc) aa $I bb"
     echo '#define OLDTOY(...)'
     if [ "$I" == A ]
     then
       cat "$GENDIR"/config.h
     else
       $SED '/USE_.*([^)]*)$/s/$/ __VA_ARGS__/' "$GENDIR"/config.h
     fi
     echo '#include "lib/toyflags.h"'
     cat "$GENDIR"/newtoys.h

     # Run result through preprocessor, glue together " " gaps leftover from USE
     # macros, delete comment lines, print any line with a quoted optstring,
     # turn any non-quoted opstring (NULL or 0) into " " (because fscanf can't
     # handle "" with nothing in it, and mkflags uses that).

     ) | ${CROSS_COMPILE}${CC} -E - | \
     $SED -n -e 's/" *"//g;/^#/d;t clear;:clear;s/"/"/p;t;s/\( [AB] \).*/\1 " "/p'

   # Sort resulting line pairs and glue them together into triplets of
   #   command "flags" "allflags"
   # to feed into mkflags C program that outputs actual flag macros
   # If no pair (because command's disabled in config), use " " for flags
   # so allflags can define the appropriate zero macros.

   done | sort -s | $SED -n -e 's/ A / /;t pair;h;s/\([^ ]*\).*/\1 " "/;x' \
     -e 'b single;:pair;h;n;:single;s/[^ ]* B //;H;g;s/\n/ /;p' | \
     tee "$GENDIR"/flags.raw | "$UNSTRIPPED"/mkflags > "$GENDIR"/flags.h || exit 1
 fi

 # Extract global structure definitions and flag definitions from toys/*/*.c

 function getglobals()
 {
   for i in toys/*/*.c
   do
     # alas basename -s isn't in posix yet.
     NAME="$(echo $i | $SED 's@.*/\(.*\)\.c@\1@')"
     DATA="$($SED -n -e '/^GLOBALS(/,/^)/b got;b;:got' \
             -e 's/^GLOBALS(/_data {/' \
             -e 's/^)/};/' -e 'p' $i)"
     [ ! -z "$DATA" ] && echo -e "// $i\n\nstruct $NAME$DATA\n"
   done
 }

 if isnewer "$GENDIR"/globals.h toys
 then
   echo -n "$GENDIR/globals.h "
   GLOBSTRUCT="$(getglobals)"
   (
     echo "$GLOBSTRUCT"
     echo
     echo "extern union global_union {"
     echo "$GLOBSTRUCT" | \
       $SED -n 's/struct \(.*\)_data {/	struct \1_data \1;/p'
     echo "} this;"
   ) > "$GENDIR"/globals.h
 fi

 if [ ! -f "$UNSTRIPPED"/mktags ] || [ "$UNSTRIPPED"/mktags -ot scripts/mktags.c ]
 then
   do_loudly $HOSTCC scripts/mktags.c -o "$UNSTRIPPED"/mktags || exit 1
 fi

 if isnewer "$GENDIR"/tags.h toys
 then
   echo -n "$GENDIR/tags.h "

   $SED -n '/TAGGED_ARRAY(/,/^)/{s/.*TAGGED_ARRAY[(]\([^,]*\),/\1/;p}' \
     toys/*/*.c lib/*.c | "$UNSTRIPPED"/mktags > "$GENDIR"/tags.h
 fi

 if [ ! -f "$UNSTRIPPED"/config2help ] || [ "$UNSTRIPPED"/config2help -ot scripts/config2help.c ]
 then
   do_loudly $HOSTCC scripts/config2help.c -o "$UNSTRIPPED"/config2help || exit 1
 fi
 if isnewer "$GENDIR"/help.h "$GENDIR"/Config.in
 then
   echo "$GENDIR/help.h"
   "$UNSTRIPPED"/config2help Config.in $KCONFIG_CONFIG > "$GENDIR"/help.h || exit 1
 fi

 [ ! -z "$NOBUILD" ] && exit 0

 echo -n "Compile $OUTNAME"
 [ ! -z "$V" ] && echo
 DOTPROG=.

 # This is a parallel version of: do_loudly $BUILD $FILES $LINK || exit 1

 # Any headers newer than the oldest generated/obj file?
 X="$(ls -1t "$GENDIR"/obj/* 2>/dev/null | tail -n 1)"
 # TODO: redo this
 if [ ! -e "$X" ] || [ ! -z "$(find toys -name "*.h" -newer "$X")" ]
 then
   rm -rf "$GENDIR"/obj && mkdir -p "$GENDIR"/obj || exit 1
 else
   rm -f "$GENDIR"/obj/main.o || exit 1
 fi

 # build each generated/obj/*.o file in parallel

 unset PENDING LNKFILES CLICK
 DONE=0
 COUNT=0

 for i in lib/*.c click $TOYFILES
 do
   [ "$i" == click ] && CLICK=1 && continue

   X=${i/lib\//lib_}
   X=${X##*/}
   OUT="$GENDIR/obj/${X%%.c}.o"
   LNKFILES="$LNKFILES $OUT"

   # Library files don't need to be rebuilt if older than .config.
   # ($TOYFILES contents can depend on CONFIG symbols, lib/*.c never should.)

   [ "$OUT" -nt "$i" ] && [ -z "$CLICK" -o "$OUT" -nt "$KCONFIG_CONFIG" ] &&
     continue

   do_loudly $BUILD -c $i -o $OUT &

   # ratelimit to $CPUS many parallel jobs, detecting errors
   [ $((++COUNT)) -ge $CPUS ] && { wait $DASHN; DONE=$?; : $((--COUNT)); }
   [ $DONE -ne 0 ] && break
 done
 # wait for all background jobs, detecting errors

 while [ $((COUNT--)) -gt 0 ]
 do
   wait $DASHN;
   DONE=$((DONE+$?))
 done
 [ $DONE -ne 0 ] && exit 1

 UNSTRIPPED="$UNSTRIPPED/${OUTNAME/*\//}"
 do_loudly $BUILD $LNKFILES $LINK -o "$UNSTRIPPED" || exit 1
 if [ ! -z "$NOSTRIP" ] ||
   ! do_loudly ${CROSS_COMPILE}${STRIP} "$UNSTRIPPED" -o "$OUTNAME"
 then
   [ -z "$NOSTRIP" ] && echo "strip failed, using unstripped"
   rm -f "$OUTNAME" &&
   cp "$UNSTRIPPED" "$OUTNAME" || exit 1
 fi

 # gcc 4.4's strip command is buggy, and doesn't set the executable bit on
 # its output the way SUSv4 suggests it do so. While we're at it, make sure
 # we don't have the "w" bit set so things like bzip2's "cp -f" install don't
 # overwrite our binary through the symlink.
 do_loudly chmod 555 "$OUTNAME" || exit 1

 echo
	#!/bin/bash

	# Grab default values for $CFLAGS and such.

	set -o pipefail
	source scripts/portability.sh

	# Default to running one more parallel cc instance than we have processors
	: ${CPUS:=$(($(nproc 2>/dev/null \|\| sysctl -n hw.ncpu 2>/dev/null)+1))}

	# Respond to V= by echoing command lines as well as running them
	DOTPROG=
	do_loudly()
	{
	[ ! -z "$V" ] && echo "$@" \|\| echo -n "$DOTPROG"
	"$@"
	}

	# Is anything under directory $2 newer than file $1
	isnewer()
	{
	CHECK="$1"
	shift
	[ ! -z "$(find "$@" -newer "$CHECK" 2>/dev/null \|\| echo yes)" ]
	}

	echo "Generate headers from toys//.c..."

	mkdir -p "${UNSTRIPPED:=$GENDIR/unstripped}"

	if isnewer "$GENDIR"/Config.in toys \|\| isnewer "$GENDIR"/Config.in Config.in
	then
	echo "Extract configuration information from toys/*.c files..."
	scripts/genconfig.sh
	fi

	# Create a list of all the commands toybox can provide. Note that the first
	# entry is out of order on purpose (the toybox multiplexer command must be the
	# first element of the array). The rest must be sorted in alphabetical order
	# for fast binary search.

	if isnewer "$GENDIR"/newtoys.h toys
	then
	echo -n "$GENDIR/newtoys.h "

	echo "USE_TOYBOX(NEWTOY(toybox, NULL, TOYFLAG_STAYROOT))" > "$GENDIR"/newtoys.h
	$SED -n -e 's/^USE_[A-Z0-9_](/&/p' toys//*.c \
	\| $SED 's/\(.TOY(\)\([^,]\),\(.*\)/\2 \1\2,\3/' \| sort -s -k 1,1 \
	\| $SED 's/[^ ]* //' >> "$GENDIR"/newtoys.h
	[ $? -ne 0 ] && exit 1
	fi

	[ ! -z "$V" ] && echo "Which C files to build..."

	# Extract a list of toys//.c files to compile from the data in $KCONFIG_CONFIG
	# (First command names, then filenames with relevant {NEW,OLD}TOY() macro.)

	[ -d ".git" ] && GITHASH="-DTOYBOX_VERSION=\"$(git describe --tags --abbrev=12 2>/dev/null)\""
	TOYFILES="$($SED -n 's/^CONFIG_\([^=]\)=./\1/p' "$KCONFIG_CONFIG" \| xargs \| tr ' [A-Z]' '\|[a-z]')"
	TOYFILES="main.c $(egrep -l "TOY[(]($TOYFILES)[ ,]" toys//.c \| xargs)"
	BUILD="$(echo ${CROSS_COMPILE}${CC} $CFLAGS -I . $OPTIMIZE $GITHASH)"

	if [ "${TOYFILES/pending//}" != "$TOYFILES" ]
	then
	echo -e "\n\033[1;31mwarning: using unfinished code from toys/pending\033[0m"
	fi

	genbuildsh()
	{
	# Write a canned build line for use on crippled build machines.

	echo -e "#!/bin/sh\n\nPATH='$PATH'\nBUILD='$BUILD'\nLINK='$LINK'\n"
	echo -e "\$BUILD lib/*.c $TOYFILES \$LINK -o $OUTNAME"
	}

	if ! cmp -s <(genbuildsh 2>/dev/null \| head -n 4 ; echo LINK="'"$LDOPTIMIZE $LDFLAGS) \
	<(head -n 5 "$GENDIR"/build.sh 2>/dev/null \| $SED '5s/ -o .*//')
	then
	echo -n "Library probe"

	# --as-needed removes libraries we don't use any symbols out of, but the
	# compiler has no way to ignore a library that doesn't exist, so detect
	# and skip nonexistent libraries for it.

	> "$GENDIR"/optlibs.dat
	for i in util crypt m resolv selinux smack attr crypto z log iconv tls ssl
	do
	echo "int main(int argc, char *argv[]) {return 0;}" \| \
	${CROSS_COMPILE}${CC} $CFLAGS $LDFLAGS -xc - -o "$GENDIR"/libprobe -l$i > /dev/null 2>/dev/null &&
	echo -l$i >> "$GENDIR"/optlibs.dat
	echo -n .
	done
	rm -f "$GENDIR"/libprobe
	echo
	fi

	# LINK needs optlibs.dat, above

	LINK="$(echo $LDOPTIMIZE $LDFLAGS $(cat "$GENDIR"/optlibs.dat))"
	genbuildsh > "$GENDIR"/build.sh && chmod +x "$GENDIR"/build.sh \|\| exit 1

	#TODO: "make $SED && make" doesn't regenerate config.h because diff .config
	if true #isnewer "$GENDIR"/config.h "$KCONFIG_CONFIG"
	then
	echo "Make $GENDIR/config.h from $KCONFIG_CONFIG."

	# This long and roundabout sed invocation is to make old versions of sed
	# happy. New ones have '\n' so can replace one line with two without all
	# the branches and tedious mucking about with hyperspace.
	# TODO: clean this up to use modern stuff.

	$SED -n \
	-e 's/^# CONFIG_\(.\) is not set./\1/' \
	-e 't notset' \
	-e 's/^CONFIG_\(.\)=y./\1/' \
	-e 't isset' \
	-e 's/^CONFIG_\([^=]\)=\(.\)/#define CFG_\1 \2/p' \
	-e 'd' \
	-e ':notset' \
	-e 'h' \
	-e 's/.*/#define CFG_& 0/p' \
	-e 'g' \
	-e 's/.*/#define USE_&(...)/p' \
	-e 'd' \
	-e ':isset' \
	-e 'h' \
	-e 's/.*/#define CFG_& 1/p' \
	-e 'g' \
	-e 's/.*/#define USE_&(...) __VA_ARGS__/p' \
	$KCONFIG_CONFIG > "$GENDIR"/config.h \|\| exit 1
	fi

	if [ ! -f "$GENDIR"/mkflags ] \|\| [ "$GENDIR"/mkflags -ot scripts/mkflags.c ]
	then
	do_loudly $HOSTCC scripts/mkflags.c -o "$UNSTRIPPED"/mkflags \|\| exit 1
	fi

	# Process config.h and newtoys.h to generate FLAG_x macros. Note we must
	# always #define the relevant macro, even when it's disabled, because we
	# allow multiple NEWTOY() in the same C file. (When disabled the FLAG is 0,
	# so flags&0 becomes a constant 0 allowing dead code elimination.)

	if isnewer "$GENDIR"/flags.h toys "$KCONFIG_CONFIG"
	then
	echo -n "$GENDIR/flags.h "

	# Parse files through C preprocessor twice, once to get flags for current
	# .config and once to get flags for allyesconfig
	for I in A B
	do
	(
	# define macros and select header files with option string data

	echo "#define NEWTOY(aa,bb,cc) aa $I bb"
	echo '#define OLDTOY(...)'
	if [ "$I" == A ]
	then
	cat "$GENDIR"/config.h
	else
	$SED '/USE_.([^)])$/s/$/ __VA_ARGS__/' "$GENDIR"/config.h
	fi
	echo '#include "lib/toyflags.h"'
	cat "$GENDIR"/newtoys.h

	# Run result through preprocessor, glue together " " gaps leftover from USE
	# macros, delete comment lines, print any line with a quoted optstring,
	# turn any non-quoted opstring (NULL or 0) into " " (because fscanf can't
	# handle "" with nothing in it, and mkflags uses that).

	) \| ${CROSS_COMPILE}${CC} -E - \| \
	$SED -n -e 's/" "//g;/^#/d;t clear;:clear;s/"/"/p;t;s/\( [AB] \)./\1 " "/p'

	# Sort resulting line pairs and glue them together into triplets of
	# command "flags" "allflags"
	# to feed into mkflags C program that outputs actual flag macros
	# If no pair (because command's disabled in config), use " " for flags
	# so allflags can define the appropriate zero macros.

	done \| sort -s \| $SED -n -e 's/ A / /;t pair;h;s/\([^ ]\)./\1 " "/;x' \
	-e 'b single;:pair;h;n;:single;s/[^ ]* B //;H;g;s/\n/ /;p' \| \
	tee "$GENDIR"/flags.raw \| "$UNSTRIPPED"/mkflags > "$GENDIR"/flags.h \|\| exit 1
	fi

	# Extract global structure definitions and flag definitions from toys//.c

	function getglobals()
	{
	for i in toys//.c
	do
	# alas basename -s isn't in posix yet.
	NAME="$(echo $i \| $SED 's@./\(.\)\.c@\1@')"
	DATA="$($SED -n -e '/^GLOBALS(/,/^)/b got;b;:got' \
	-e 's/^GLOBALS(/_data {/' \
	-e 's/^)/};/' -e 'p' $i)"
	[ ! -z "$DATA" ] && echo -e "// $i\n\nstruct $NAME$DATA\n"
	done
	}

	if isnewer "$GENDIR"/globals.h toys
	then
	echo -n "$GENDIR/globals.h "
	GLOBSTRUCT="$(getglobals)"
	(
	echo "$GLOBSTRUCT"
	echo
	echo "extern union global_union {"
	echo "$GLOBSTRUCT" \| \
	$SED -n 's/struct \(.*\)_data {/ struct \1_data \1;/p'
	echo "} this;"
	) > "$GENDIR"/globals.h
	fi

	if [ ! -f "$UNSTRIPPED"/mktags ] \|\| [ "$UNSTRIPPED"/mktags -ot scripts/mktags.c ]
	then
	do_loudly $HOSTCC scripts/mktags.c -o "$UNSTRIPPED"/mktags \|\| exit 1
	fi

	if isnewer "$GENDIR"/tags.h toys
	then
	echo -n "$GENDIR/tags.h "

	$SED -n '/TAGGED_ARRAY(/,/^)/{s/.TAGGED_ARRAY[(]\([^,]\),/\1/;p}' \
	toys//.c lib/*.c \| "$UNSTRIPPED"/mktags > "$GENDIR"/tags.h
	fi

	if [ ! -f "$UNSTRIPPED"/config2help ] \|\| [ "$UNSTRIPPED"/config2help -ot scripts/config2help.c ]
	then
	do_loudly $HOSTCC scripts/config2help.c -o "$UNSTRIPPED"/config2help \|\| exit 1
	fi
	if isnewer "$GENDIR"/help.h "$GENDIR"/Config.in
	then
	echo "$GENDIR/help.h"
	"$UNSTRIPPED"/config2help Config.in $KCONFIG_CONFIG > "$GENDIR"/help.h \|\| exit 1
	fi

	[ ! -z "$NOBUILD" ] && exit 0

	echo -n "Compile $OUTNAME"
	[ ! -z "$V" ] && echo
	DOTPROG=.

	# This is a parallel version of: do_loudly $BUILD $FILES $LINK \|\| exit 1

	# Any headers newer than the oldest generated/obj file?
	X="$(ls -1t "$GENDIR"/obj/* 2>/dev/null \| tail -n 1)"
	# TODO: redo this
	if [ ! -e "$X" ] \|\| [ ! -z "$(find toys -name "*.h" -newer "$X")" ]
	then
	rm -rf "$GENDIR"/obj && mkdir -p "$GENDIR"/obj \|\| exit 1
	else
	rm -f "$GENDIR"/obj/main.o \|\| exit 1
	fi

	# build each generated/obj/*.o file in parallel

	unset PENDING LNKFILES CLICK
	DONE=0
	COUNT=0

	for i in lib/*.c click $TOYFILES
	do
	[ "$i" == click ] && CLICK=1 && continue

	X=${i/lib\//lib_}
	X=${X##*/}
	OUT="$GENDIR/obj/${X%%.c}.o"
	LNKFILES="$LNKFILES $OUT"

	# Library files don't need to be rebuilt if older than .config.
	# ($TOYFILES contents can depend on CONFIG symbols, lib/*.c never should.)

	[ "$OUT" -nt "$i" ] && [ -z "$CLICK" -o "$OUT" -nt "$KCONFIG_CONFIG" ] &&
	continue

	do_loudly $BUILD -c $i -o $OUT &

	# ratelimit to $CPUS many parallel jobs, detecting errors
	[ $((++COUNT)) -ge $CPUS ] && { wait $DASHN; DONE=$?; : $((--COUNT)); }
	[ $DONE -ne 0 ] && break
	done
	# wait for all background jobs, detecting errors

	while [ $((COUNT--)) -gt 0 ]
	do
	wait $DASHN;
	DONE=$((DONE+$?))
	done
	[ $DONE -ne 0 ] && exit 1

	UNSTRIPPED="$UNSTRIPPED/${OUTNAME/*\//}"
	do_loudly $BUILD $LNKFILES $LINK -o "$UNSTRIPPED" \|\| exit 1
	if [ ! -z "$NOSTRIP" ] \|\|
	! do_loudly ${CROSS_COMPILE}${STRIP} "$UNSTRIPPED" -o "$OUTNAME"
	then
	[ -z "$NOSTRIP" ] && echo "strip failed, using unstripped"
	rm -f "$OUTNAME" &&
	cp "$UNSTRIPPED" "$OUTNAME" \|\| exit 1
	fi

	# gcc 4.4's strip command is buggy, and doesn't set the executable bit on
	# its output the way SUSv4 suggests it do so. While we're at it, make sure
	# we don't have the "w" bit set so things like bzip2's "cp -f" install don't
	# overwrite our binary through the symlink.
	do_loudly chmod 555 "$OUTNAME" \|\| exit 1

	echo