}
check_cc() {
- local tempname="/tmp/temp.$$.$RANDOM"
+ tempname="$(mktemp tmp.XXXXXXXXXX)"
+ echo "int main(int argc,char**argv){return argv?argc:0;}" >"$tempname".c
# Can use "-o /dev/null", but older gcc tend to *unlink it* on failure! :(
- # "-xc": C language. "/dev/null" is an empty source file.
- if $CC $1 -shared -xc /dev/null -o "$tempname".o >/dev/null 2>&1; then
- echo "$1";
- else
- echo "$2";
- fi
- rm "$tempname".o 2>/dev/null
+ # Was using "-xc /dev/null", but we need a valid C program.
+ # "eval" may be needed if CFLAGS can contain
+ # '... -D"BB_VER=KBUILD_STR(1.N.M)" ...'
+ # and we need shell to process quotes!
+ $CC $CFLAGS $LDFLAGS $1 "$tempname".c -o "$tempname" >/dev/null 2>&1
+ exitcode=$?
+ rm -f "$tempname" "$tempname".c "$tempname".o
+ return $exitcode
}
check_libc_is_glibc() {
- local tempname="/tmp/temp.$$.$RANDOM"
+ tempname="$(mktemp tmp.XXXXXXXXXX)"
echo "\
#include <stdlib.h>
/* Apparently uclibc defines __GLIBC__ (compat trick?). Oh well. */
syntax error here
#endif
" >"$tempname".c
- if $CC "$tempname".c -c -o "$tempname".o >/dev/null 2>&1; then
- echo "$2";
- else
- echo "$1";
- fi
- rm "$tempname".c "$tempname".o 2>/dev/null
+ ! $CC $CFLAGS "$tempname".c -c -o "$tempname".o >/dev/null 2>&1
+ exitcode=$?
+ rm -f "$tempname" "$tempname".c "$tempname".o
+ return $exitcode
}
EXE="$1"
LDLIBS="$7"
# The --sort-section option is not supported by older versions of ld
-SORT_SECTION=`check_cc "-Wl,--sort-section,alignment" ""`
+SORT_SECTION="-Wl,--sort-section,alignment"
+if ! check_cc "-Wl,--sort-section,alignment"; then
+ echo "Your linker does not support --sort-section,alignment"
+ SORT_SECTION=""
+fi
START_GROUP="-Wl,--start-group"
END_GROUP="-Wl,--end-group"
-INFO_OPTS="-Wl,--warn-common -Wl,-Map,$EXE.map -Wl,--verbose"
+INFO_OPTS() {
+ echo "-Wl,--warn-common -Wl,-Map,$EXE.map -Wl,--verbose"
+}
# gold may not support --sort-common (yet)
-SORT_COMMON=`check_cc "-Wl,--sort-common" ""`
+SORT_COMMON="-Wl,--sort-common"
+if ! check_cc "-Wl,--sort-common"; then
+ echo "Your linker does not support --sort-common"
+ SORT_COMMON=""
+fi
# Static linking against glibc produces buggy executables
# (glibc does not cope well with ld --gc-sections).
# See sources.redhat.com/bugzilla/show_bug.cgi?id=3400
# Note that glibc is unsuitable for static linking anyway.
# We are removing -Wl,--gc-sections from link command line.
-GC_SECTIONS=`(
-. ./.config
-if test x"$CONFIG_STATIC" = x"y"; then
- check_libc_is_glibc "" "-Wl,--gc-sections"
-else
- echo "-Wl,--gc-sections"
+GC_SECTIONS="-Wl,--gc-sections"
+if (. ./.config && test x"$CONFIG_STATIC" = x"y") then
+ if check_libc_is_glibc; then
+ echo "Static linking against glibc, can't use --gc-sections"
+ GC_SECTIONS=""
+ fi
fi
-)`
-
# The --gc-sections option is not supported by older versions of ld
if test -n "$GC_SECTIONS"; then
- GC_SECTIONS=`check_cc "$GC_SECTIONS" ""`
+ if ! check_cc "$GC_SECTIONS"; then
+ echo "Your linker does not support $GC_SECTIONS"
+ GC_SECTIONS=""
+ fi
fi
# Sanitize lib list (dups, extra spaces etc)
# First link with all libs. If it fails, bail out
echo "Trying libraries: $LDLIBS"
# "lib1 lib2 lib3" -> "-llib1 -llib2 -llib3"
-l_list=`echo "$LDLIBS" | sed -e 's/ / -l/g' -e 's/^/-l/' -e 's/^-l$//'`
+l_list=`echo " $LDLIBS " | sed -e 's: \([^- ][^ ]*\): -l\1:g'`
test "x$l_list" != "x" && l_list="$START_GROUP $l_list $END_GROUP"
try $CC $CFLAGS $LDFLAGS \
-o $EXE \
|| {
echo "Failed: $l_list"
cat $EXE.out
+ echo 'Note: if build needs additional libraries, put them in CONFIG_EXTRA_LDLIBS.'
+ echo 'Example: CONFIG_EXTRA_LDLIBS="pthread dl tirpc audit pam"'
exit 1
}
# Stop when no lib can be removed.
while test "$LDLIBS"; do
$debug && echo "Trying libraries: $LDLIBS"
- all_needed=true
- last_needed=false
+ dropped_non_first_lib=false
+ first_lib=true
for one in $LDLIBS; do
without_one=`echo " $LDLIBS " | sed "s/ $one / /g" | xargs`
# "lib1 lib2 lib3" -> "-llib1 -llib2 -llib3"
- l_list=`echo "$without_one" | sed -e 's/ / -l/g' -e 's/^/-l/' -e 's/^-l$//'`
+ l_list=`echo " $without_one " | sed -e 's: \([^- ][^ ]*\): -l\1:g'`
test x"$l_list" != x"" && l_list="$START_GROUP $l_list $END_GROUP"
$debug && echo "Trying -l options: '$l_list'"
try $CC $CFLAGS $LDFLAGS \
if test $? = 0; then
echo " Library $one is not needed, excluding it"
LDLIBS="$without_one"
- all_needed=false
- last_needed=false
+ $first_lib || dropped_non_first_lib=true
else
echo " Library $one is needed, can't exclude it (yet)"
- last_needed=true
+ first_lib=false
fi
done
- # All libs were needed, can't remove any
- $all_needed && break
- # Optimization: was the last tried lib needed?
- if $last_needed; then
- # Was it the only one lib left? Don't test again then.
- { echo "$LDLIBS" | grep -q ' '; } || break
- fi
+ # We can stop trying to drop libs if either all libs were needed,
+ # or we excluded only the _first_ few.
+ # (else: we dropped some intermediate lib(s), maybe now we can succeed
+ # in dropping some of the preceding ones)
+ $dropped_non_first_lib || break
done
# Make the binary with final, minimal list of libs
echo "Final link with: ${LDLIBS:-<none>}"
-l_list=`echo "$LDLIBS" | sed -e 's/ / -l/g' -e 's/^/-l/' -e 's/^-l$//'`
+l_list=`echo " $LDLIBS " | sed -e 's: \([^- ][^ ]*\): -l\1:g'`
test "x$l_list" != "x" && l_list="$START_GROUP $l_list $END_GROUP"
# --verbose gives us gobs of info to stdout (e.g. linker script used)
if ! test -f busybox_ldscript; then
$GC_SECTIONS \
$START_GROUP $O_FILES $A_FILES $END_GROUP \
$l_list \
- $INFO_OPTS \
+ `INFO_OPTS` \
|| {
cat $EXE.out
exit 1
# *(.bss SORT_BY_ALIGNMENT(.bss.*) .gnu.linkonce.b.*)
# This will eliminate most of the padding (~3kb).
# Hmm, "ld --sort-section alignment" should do it too.
+ #
+ # There is a ld hack which is meant to decrease disk usage
+ # at the cost of more RAM usage (??!!) in standard ld script:
+ # /* Adjust the address for the data segment. We want to adjust up to
+ # the same address within the page on the next page up. */
+ # . = ALIGN (0x1000) - ((0x1000 - .) & (0x1000 - 1)); . = DATA_SEGMENT_ALIGN (0x1000, 0x1000);
+ # Replace it with:
+ # . = ALIGN (0x1000); . = DATA_SEGMENT_ALIGN (0x1000, 0x1000);
+ # to unconditionally align .data to the next page boundary,
+ # instead of "next page, plus current offset in this page"
try $CC $CFLAGS $LDFLAGS \
-o $EXE \
$SORT_COMMON \
-Wl,-T,busybox_ldscript \
$START_GROUP $O_FILES $A_FILES $END_GROUP \
$l_list \
- $INFO_OPTS \
+ `INFO_OPTS` \
|| {
cat $EXE.out
exit 1
}
ln -s "libbusybox.so.$BB_VER" "$sharedlib_dir"/libbusybox.so 2>/dev/null
+ # Yes, "ld -shared -static" is a thing. It's a shared library which is itself static.
+ LBB_STATIC=""
+ test "$CONFIG_FEATURE_LIBBUSYBOX_STATIC" = y && LBB_STATIC="-Wl,-static"
+
EXE="$sharedlib_dir/libbusybox.so.${BB_VER}_unstripped"
try $CC $CFLAGS $LDFLAGS \
-o $EXE \
- -shared -fPIC \
+ -shared -fPIC $LBB_STATIC \
-Wl,--enable-new-dtags \
-Wl,-z,combreloc \
-Wl,-soname="libbusybox.so.$BB_VER" \
$SORT_SECTION \
$START_GROUP $A_FILES $END_GROUP \
$l_list \
- $INFO_OPTS \
+ `INFO_OPTS` \
|| {
echo "Linking $EXE failed"
cat $EXE.out
$GC_SECTIONS \
$START_GROUP $O_FILES $END_GROUP \
-L"$sharedlib_dir" -lbusybox \
- $INFO_OPTS \
+ $l_list \
+ `INFO_OPTS` \
|| {
echo "Linking $EXE failed"
cat $EXE.out
if test "$CONFIG_FEATURE_INDIVIDUAL" = y; then
echo "Linking individual applets against libbusybox (see $sharedlib_dir/*)"
- gcc -DNAME_MAIN_CNAME -E -include include/autoconf.h include/applets.h \
+ gcc -DNAME_MAIN -E -include include/autoconf.h include/applets.h \
| grep -v "^#" \
- | grep -v "^$" \
+ | grep -v "^ *$" \
> applet_lst.tmp
while read name main junk; do
}
rm -- "$sharedlib_dir/applet.c" $EXE.out
$STRIP -s --remove-section=.note --remove-section=.comment $EXE
+ # Let user see that we do something - list the names of created binaries:
+ echo "$EXE"
done <applet_lst.tmp
fi
projects / oweals / busybox.git / blobdiff