1#!/bin/sh
2# SPDX-License-Identifier: GPL-2.0
3#
4# Check whether linker can handle cross-segment @segrel():
5#
6CPPFLAGS=""
7CC=$1
8OBJDUMP=$2
9READELF=$3
10dir=$(dirname $0)
11tmp=${TMPDIR:-/tmp}
12out=$tmp/out$$
13
14# Check whether cross-segment segment-relative relocs work fine.  We need
15# that for building the gate DSO:
16
17$CC -nostdlib -static -Wl,-T$dir/check-segrel.lds $dir/check-segrel.S -o $out
18res=$($OBJDUMP --full --section .rodata $out | fgrep 000 | cut -f3 -d' ')
19rm -f $out
20if [ $res != 00000a00 ]; then
21    CPPFLAGS="$CPPFLAGS -DHAVE_BUGGY_SEGREL"
22    cat >&2 <<EOF
23warning: your linker cannot handle cross-segment segment-relative relocations.
24         please upgrade to a newer version (it is safe to use this linker, but
25         the kernel will be bigger than strictly necessary).
26EOF
27fi
28
29# Check whether .align inside a function works as expected.
30
31$CC -c $dir/check-text-align.S -o $out
32$READELF -u $out | fgrep -q 'prologue(rlen=12)'
33res=$?
34rm -f $out
35if [ $res -eq 0 ]; then
36    CPPFLAGS="$CPPFLAGS -DHAVE_WORKING_TEXT_ALIGN"
37fi
38
39if ! $CC -c $dir/check-model.c -o $out 2>&1 | grep  __model__ | grep -q attrib
40then
41    CPPFLAGS="$CPPFLAGS -DHAVE_MODEL_SMALL_ATTRIBUTE"
42fi
43rm -f $out
44
45# Check whether assembler supports .serialize.{data,instruction} directive.
46
47$CC -c $dir/check-serialize.S -o $out 2>/dev/null
48res=$?
49rm -f $out
50if [ $res -eq 0 ]; then
51    CPPFLAGS="$CPPFLAGS -DHAVE_SERIALIZE_DIRECTIVE"
52fi
53
54echo $CPPFLAGS
55