[v4,0/4] Remove --with-default-link option

  The vtables hardening is not enabled with --with-default-link=no
(tst-relro-libc fails [1]) and with --with-default-link=yes it also
requires ld.bfd to be available [2].  Furthermore, only lld 15
supports custom RELRO sections in linker script, even though older
versions do support building glibc for some architectures.

The patchset removes the --with-default-link by replacing
libc_freeres_ptrs and libc_subfreeres with weak function calls, and by
refactoring the vtables hardening with an array placed directly in the
RELRO segment.

[1] https://sourceware.org/bugzilla/show_bug.cgi?id=25812
[2] https://sourceware.org/git/?p=glibc.git;a=commit;h=2ae7990542e1955097aa21943e416dec70f867fa

Changes from v3:
- Remove pragma weak diretive for _IO_default_* and _IO_wdefault_*
  symbols.

Changes from v2:
- Add pragma weak for weakly called function at malloc/set-freeres.c.
- Remove IO_str*, IO_new_file*, and IO_old from pragma weak directive.

Adhemerval Zanella Netto (4):
  Move libc_freeres_ptrs and libc_subfreeres to hidden/weak functions
  libio: Remove the usage of __libc_IO_vtables
  Remove --with-default-link configure option
  Remove set-hooks.h from generic includes

 INSTALL                                       |   6 -
 Makerules                                     |  52 +-
 config.make.in                                |   1 -
 configure                                     |  13 -
 configure.ac                                  |   7 -
 crypt/md5-crypt.c                             |   7 +-
 crypt/sha256-crypt.c                          |   7 +-
 crypt/sha512-crypt.c                          |   7 +-
 dlfcn/dlerror.h                               |   1 -
 elf/Makefile                                  |  18 +-
 elf/dl-libc.c                                 |   5 +-
 grp/fgetgrent.c                               |   5 +-
 gshadow/fgetsgent.c                           |   5 +-
 {include => hurd}/set-hooks.h                 |   0
 iconv/gconv_cache.c                           |   3 +-
 iconv/gconv_conf.c                            |   3 +-
 iconv/gconv_db.c                              |   6 +-
 iconv/gconv_dl.c                              |   5 +-
 iconvdata/extra-module.mk                     |   2 +-
 include/libc-symbols.h                        |  91 +---
 include/set-freeres.h                         | 142 ++++++
 inet/getnameinfo.c                            |   5 +-
 inet/getnetgrent.c                            |   5 +-
 inet/rcmd.c                                   |   5 +-
 inet/rexec.c                                  |   5 +-
 intl/dcigettext.c                             |   3 +-
 intl/finddomain.c                             |   2 +-
 intl/loadmsgcat.c                             |   1 -
 intl/localealias.c                            |  15 +-
 libio/Makefile                                |   2 +
 libio/fcloseall.c                             |   1 +
 libio/fileops.c                               |  81 +--
 libio/genops.c                                |   8 +-
 libio/iofopncook.c                            |  60 +--
 libio/iopopen.c                               |  25 -
 libio/libio-macros.sym                        |   7 +
 libio/libioP.h                                | 137 ++++-
 libio/memstream.c                             |  32 +-
 libio/oldfileops.c                            |  23 -
 libio/oldiopopen.c                            |  23 -
 libio/stdio.c                                 |   3 +
 libio/strfile.h                               |   2 -
 libio/strops.c                                |  24 -
 libio/tst-vtables-interposed.c                |   5 +
 libio/vtables.c                               | 478 ++++++++++++++++++
 libio/wfileops.c                              |  79 +--
 libio/wmemstream.c                            |  32 +-
 libio/wstrops.c                               |  24 -
 locale/loadarchive.c                          |   2 +-
 locale/localeinfo.h                           |   4 +-
 locale/setlocale.c                            |   4 +-
 login/getutent.c                              |   5 +-
 login/getutid.c                               |   6 +-
 login/getutline.c                             |   5 +-
 malloc/set-freeres.c                          | 156 +++++-
 malloc/thread-freeres.c                       |   9 +-
 manual/install.texi                           |   6 -
 misc/efgcvt-template.c                        |   5 +-
 misc/efgcvt.c                                 |   1 +
 misc/fstab.c                                  |   3 +-
 misc/hsearch.c                                |   4 -
 misc/mntent.c                                 |   5 +-
 misc/qefgcvt.c                                |   1 +
 misc/unwind-link.c                            |   2 +-
 nptl/nptlfreeres.c                            |   1 -
 nscd/nscd_getgr_r.c                           |   3 +-
 nscd/nscd_gethst_r.c                          |   3 +-
 nscd/nscd_getpw_r.c                           |   3 +-
 nscd/nscd_getserv_r.c                         |   3 +-
 nscd/nscd_netgroup.c                          |   3 +-
 nss/getXXbyYY.c                               |   7 +-
 nss/getXXent.c                                |   7 +-
 nss/nss_action.c                              |   2 +-
 nss/nss_action.h                              |   3 -
 nss/nss_database.c                            |   2 +-
 nss/nss_database.h                            |   3 -
 nss/nss_module.c                              |   2 +-
 nss/nss_module.h                              |   3 -
 posix/regcomp.c                               |   3 +-
 posix/register-atfork.c                       |   3 +-
 pwd/fgetpwent.c                               |   5 +-
 resolv/gai_misc.c                             |   6 +-
 resolv/res-close.c                            |   2 -
 resolv/res_hconf.c                            |  16 +-
 resolv/resolv-internal.h                      |  14 +
 resolv/resolv_conf.c                          |   3 +-
 resolv/tst-leaks2.c                           |   2 +
 rt/aio_misc.c                                 |   6 +-
 shadow/fgetspent.c                            |   5 +-
 stdio-common/printf_buffer_as_file.c          |  28 +-
 stdio-common/reg-modifier.c                   |   3 +-
 stdio-common/reg-printf.c                     |   6 +-
 stdio-common/reg-type.c                       |   6 +-
 stdio-common/wprintf_buffer_as_file.c         |  28 +-
 stdlib/exit.c                                 |   2 +-
 stdlib/fmtmsg.c                               |   3 +-
 stdlib/setenv.c                               |   3 +-
 sunrpc/clnt_perr.c                            |   4 +-
 sunrpc/rpc_thread.c                           |   1 -
 sunrpc/tst-svc_register.c                     |   6 +-
 sysdeps/generic/set-freeres-fp.h              |  19 +
 sysdeps/generic/set-freeres-os.h              |  19 +
 sysdeps/generic/set-freeres-system.h          |  27 +
 .../ldbl-128ibm-compat/ieee128-qefgcvt.c      |   1 +
 .../ldbl-128ibm-compat/set-freeres-fp.h       |  22 +
 sysdeps/mach/hurd/bits/errno.h                |   1 -
 sysdeps/posix/getaddrinfo.c                   |   5 +-
 sysdeps/posix/ttyname.c                       |   4 +-
 sysdeps/unix/sysv/linux/check_pf.c            |   3 +-
 .../unix/sysv/linux/s390/s390-32/getutent.c   |   1 +
 .../unix/sysv/linux/s390/s390-32/getutid.c    |   1 +
 .../unix/sysv/linux/s390/s390-32/getutline.c  |   1 +
 sysdeps/unix/sysv/linux/set-freeres-os.h      |  24 +
 sysdeps/unix/sysv/linux/ttyname.c             |   8 +-
 time/tzfile.c                                 |   5 +-
 time/tzset.c                                  |   3 +-
 116 files changed, 1228 insertions(+), 807 deletions(-)
 rename {include => hurd}/set-hooks.h (100%)
 create mode 100644 include/set-freeres.h
 create mode 100644 libio/libio-macros.sym
 create mode 100644 sysdeps/generic/set-freeres-fp.h
 create mode 100644 sysdeps/generic/set-freeres-os.h
 create mode 100644 sysdeps/generic/set-freeres-system.h
 create mode 100644 sysdeps/ieee754/ldbl-128ibm-compat/set-freeres-fp.h
 create mode 100644 sysdeps/unix/sysv/linux/set-freeres-os.h