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|
#!/bin/sh
debug=false
try() {
added="$1"
shift
$debug && echo "Trying: $* $added"
"$@" $added 2>busybox_ld.err
}
# Sanitize lib list (dups, extra spaces etc)
#echo "BBOX_LIB_LIST=$BBOX_LIB_LIST"
BBOX_LIB_LIST=`echo "$BBOX_LIB_LIST" | xargs -n1 | sort | uniq | xargs`
# First link with all libs. If it fails, bail out
l_list=`echo "$BBOX_LIB_LIST" | sed -e 's/ / -l/g' -e 's/^/-l/'`
echo "Trying libraries: $BBOX_LIB_LIST"
try "-Wl,--start-group $l_list -Wl,--end-group" "$@" \
|| {
echo "Failed: $* -Wl,--start-group $l_list -Wl,--end-group"
cat busybox_ld.err
exit 1
}
#### Hack disabled: conflicts with ld --verbose flag in last link phase
##### Hack: we are not supposed to know executable name,
##### but this hack cuts down link time
####mv busybox_unstripped busybox_unstripped.tmp
####mv busybox.map busybox.map.tmp
# Now try to remove each lib and build without it.
# Stop when no lib can be removed.
####ever_discarded=false
while test "$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/'`
# If l_list is just "-l" without a lib, then make sure to test the
# correct thing to fail: just using -l will fail, so the last lib
# (usually m in my case) will incorrectly be added as needed.
if test "x$without_one" != "x"; then
l_list="-Wl,--start-group $l_list -Wl,--end-group"
else
# without_one is empty, so l_list has to be empty too
l_list=""
fi
$debug && echo "Trying -l options: '$l_list'"
if try "$l_list" "$@"; then
echo "Library $one is not needed"
BBOX_LIB_LIST="$without_one"
all_needed=false
#### ever_discarded=true
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
####mv busybox_unstripped.tmp busybox_unstripped
####mv busybox.map.tmp busybox.map
####$ever_discarded && {
# 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/'`
# --verbose gives us gobs of info to stdout (e.g. linker script used)
if ! test -f busybox_ldscript; then
try "-Wl,--start-group $l_list -Wl,--end-group -Wl,--verbose" "$@" >busybox_ld.out ####|| exit 1
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 "-Wl,--start-group $l_list -Wl,--end-group -Wl,--verbose -Wl,-T -Wl,busybox_ldscript" "$@" >busybox_ld.out
fi
####}
####rm busybox_ld.err
####exit 0 # Ensure "success" exit code
|
