scripts/tools-support-relr.sh

   1 #!/bin/sh -eu
   2 # SPDX-License-Identifier: GPL-2.0
   3
   4 tmp_file=$(mktemp)
   5 trap "rm -f $tmp_file.o $tmp_file $tmp_file.bin" EXIT
   6
   7 cat << "END" | $CC -c -x c - -o $tmp_file.o >/dev/null 2>&1
   8 void *p = &p;
   9 END
  10
  11 # ld.lld before 15 did not support -z pack-relative-relocs.
  12 if ! $LD $tmp_file.o -shared -Bsymbolic --pack-dyn-relocs=relr -o $tmp_file 2>/dev/null; then
  13         $LD $tmp_file.o -shared -Bsymbolic -z pack-relative-relocs -o $tmp_file 2>&1 |
  14                 grep -q pack-relative-relocs && exit 1
  15 fi
  16
  17 # Despite printing an error message, GNU nm still exits with exit code 0 if it
  18 # sees a relr section. So we need to check that nothing is printed to stderr.
  19 test -z "$($NM $tmp_file 2>&1 >/dev/null)"
  20
  21 $OBJCOPY -O binary $tmp_file $tmp_file.bin