The last sed release had a "minor" problem which was fixed after the
release:
https://git.savannah.gnu.org/gitweb/?p=sed.git;a=commit;h=8f600f2df293d539e9e9137f6f82faa1633b97c1
- mishandling of symlinks.
There was unfortunately no new release, and this is a major issue,
because the packaged version of sed breaks buildroot (specfically the
mkusers script) with targets that contain a second level of indirection,
shortened reproducer:
```
export
TARGET=/work2/work/abc/br2_target/basesystem/abcdef_ghij/build/buildroot-fs/squashfs/target
mkdir -p $TARGET/etc/
mkdir -p $TARGET/tmp/etc/
touch $TARGET/etc/group.default
ln -sf -T ../tmp/etc/group $TARGET/etc/group
ln -sf -T ../../etc/group.default $TARGET/tmp/etc/group
sed -i --follow-symlinks -e '/^service:.*/d;' $TARGET/etc/group
unset TARGET
```
This breaks:
```
sed -i --follow-symlinks -e '/^service:.*/d;' $TARGET/etc/group
sed: couldn't readlink
/work2/work/abc/br2_target/basesystem/abcdef_ghij/build/buildroot-fs/squashfs/target/etc/../tmp/etc/../../etc/group.defaul:
No such file or directory
```
Mind the path - the "t" at the end is missing. Sed line borrowed from
buildroot.
