debug=false
-function try {
+try() {
added="$1"
shift
$debug && echo "Trying: $* $added"
- "$@" $added >/dev/null 2>&1 \
- && exit 0
+ "$@" $added 2>busybox_ld.err
}
-try "" "$@"
-try "-lm" "$@"
-try "-lcrypt" "$@"
-try "-Wl,--start-group -lcrypt -lm -Wl,--end-group" "$@"
-# It failed. Rerun & let people see the error messages
-"$@" $added
+# Sanitize lib list (dups, extra spaces etc)
+#echo "BBOX_LIB_LIST=$BBOX_LIB_LIST"
+BBOX_LIB_LIST=`echo "$BBOX_LIB_LIST" | xargs -n1 | sort | uniq | xargs`
+
+# First link with all libs. If it fails, bail out
+echo "Trying libraries: $BBOX_LIB_LIST"
+l_list=`echo "$BBOX_LIB_LIST" | sed -e 's/ / -l/g' -e 's/^/-l/' -e 's/^-l$//'`
+test "x$l_list" != "x" && l_list="-Wl,--start-group $l_list -Wl,--end-group"
+try "$l_list" "$@" \
+|| {
+ echo "Failed: $* -Wl,--start-group $l_list -Wl,--end-group"
+ cat busybox_ld.err
+ exit 1
+}
+
+# Now try to remove each lib and build without it.
+# Stop when no lib can be removed.
+while test "$BBOX_LIB_LIST"; do
+ $debug && echo "Trying libraries: $BBOX_LIB_LIST"
+ all_needed=true
+ for one in $BBOX_LIB_LIST; do
+ without_one=`echo " $BBOX_LIB_LIST " | sed "s/ $one / /g" | xargs`
+ l_list=`echo "$without_one" | sed -e 's/ / -l/g' -e 's/^/-l/' -e 's/^-l$//'`
+ test "x$l_list" != "x" && l_list="-Wl,--start-group $l_list -Wl,--end-group"
+ $debug && echo "Trying -l options: '$l_list'"
+ if try "$l_list" "$@"; then
+ echo "Library $one is not needed"
+ BBOX_LIB_LIST="$without_one"
+ all_needed=false
+ else
+ echo "Library $one is needed"
+ fi
+ done
+ # All libs were needed, can't remove any
+ $all_needed && break
+ # If there is no space char, the list has just one lib.
+ # I'm not sure that in this case lib really is 100% needed.
+ # Let's try linking without it anyway... thus commented out.
+ #{ echo "$BBOX_LIB_LIST" | grep -q ' '; } || break
+done
+
+# Make the binary with final, minimal list of libs
+echo "Final link with: $BBOX_LIB_LIST"
+l_list=`echo "$BBOX_LIB_LIST" | sed -e 's/ / -l/g' -e 's/^/-l/' -e 's/^-l$//'`
+test "x$l_list" != "x" && l_list="-Wl,--start-group $l_list -Wl,--end-group -Wl,--verbose"
+# --verbose gives us gobs of info to stdout (e.g. linker script used)
+if ! test -f busybox_ldscript; then
+ try "$l_list -Wl,--verbose" "$@" >busybox_ld.out
+else
+ echo "Custom linker script 'busybox_ldscript' found, using it"
+ # Add SORT_BY_ALIGNMENT to linker script (found in busybox_ld.out):
+ # .rodata : { *(.rodata SORT_BY_ALIGNMENT(.rodata.*) .gnu.linkonce.r.*) }
+ # *(.data SORT_BY_ALIGNMENT(.data.*) .gnu.linkonce.d.*)
+ # *(.bss SORT_BY_ALIGNMENT(.bss.*) .gnu.linkonce.b.*)
+ # This will eliminate most of the data padding (~3kb).
+ try "$l_list -Wl,--verbose -Wl,-T -Wl,busybox_ldscript" "$@" >busybox_ld.out
+fi