[PATCH v5 3/7] configure: Check for static PIE support

[Adhemerval Zanella]

On 20/01/2021 12:30, Szabolcs Nagy via Libc-alpha wrote:
> Add SUPPORT_STATIC_PIE that targets can define if they support
> static PIE. This requires PI_STATIC_AND_HIDDEN support and various
> linker features as described in
> 
>   commit 9d7a3741c9e59eba87fb3ca6b9f979befce07826
>   Add --enable-static-pie configure option to build static PIE [BZ #19574]
> 
> Currently defined on x86_64, i386 and aarch64 where static PIE is
> known to work.

LGTM, thanks.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>

> ---
>  config.h.in                  |  3 +++
>  configure                    | 13 +++++++++++++
>  configure.ac                 |  4 ++++
>  sysdeps/aarch64/configure    |  4 ++++
>  sysdeps/aarch64/configure.ac |  3 +++
>  sysdeps/i386/configure       |  3 +++
>  sysdeps/i386/configure.ac    |  3 +++
>  sysdeps/x86_64/configure     |  3 +++
>  sysdeps/x86_64/configure.ac  |  3 +++
>  9 files changed, 39 insertions(+)
> 
> diff --git a/config.h.in b/config.h.in
> index 947feeff36..06ee8ae26a 100644
> --- a/config.h.in
> +++ b/config.h.in
> @@ -259,6 +259,9 @@
>  /* Build glibc with tunables support.  */
>  #define HAVE_TUNABLES 0
>  
> +/* Define if static PIE is supported.  */
> +#undef SUPPORT_STATIC_PIE
> +
>  /* Define if static PIE is enabled.  */
>  #define ENABLE_STATIC_PIE 0
>  

Ok.

> diff --git a/configure b/configure
> index 49f7b32b52..1dc3af60b4 100755
> --- a/configure
> +++ b/configure
> @@ -6814,6 +6814,19 @@ libc_cv_multidir=`${CC-cc} $CFLAGS $CPPFLAGS -print-multi-directory`
>  
>  
>  if test "$static_pie" = yes; then
> +  # Check target support for static PIE
> +  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
> +/* end confdefs.h.  */
> +#ifndef SUPPORT_STATIC_PIE
> +# error static PIE is not supported
> +#endif
> +_ACEOF
> +if ac_fn_c_try_compile "$LINENO"; then :
> +
> +else
> +  as_fn_error $? "the architecture does not support static PIE" "$LINENO" 5
> +fi
> +rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
>    # The linker must support --no-dynamic-linker.
>    if test "$libc_cv_no_dynamic_linker" != yes; then
>      as_fn_error $? "linker support for --no-dynamic-linker needed" "$LINENO" 5


> diff --git a/configure.ac b/configure.ac
> index 341d4eeac2..dfebb8a7cc 100644
> --- a/configure.ac
> +++ b/configure.ac
> @@ -1831,6 +1831,10 @@ libc_cv_multidir=`${CC-cc} $CFLAGS $CPPFLAGS -print-multi-directory`
>  AC_SUBST(libc_cv_multidir)
>  
>  if test "$static_pie" = yes; then
> +  # Check target support for static PIE
> +  AC_COMPILE_IFELSE([AC_LANG_SOURCE([[#ifndef SUPPORT_STATIC_PIE
> +# error static PIE is not supported
> +#endif]])], , AC_MSG_ERROR([the architecture does not support static PIE]))
>    # The linker must support --no-dynamic-linker.
>    if test "$libc_cv_no_dynamic_linker" != yes; then
>      AC_MSG_ERROR([linker support for --no-dynamic-linker needed])

Ok.

> diff --git a/sysdeps/aarch64/configure b/sysdeps/aarch64/configure
> index 5f5f3cc44c..83c3a23e44 100644
> --- a/sysdeps/aarch64/configure
> +++ b/sysdeps/aarch64/configure
> @@ -6,6 +6,10 @@
>  $as_echo "#define PI_STATIC_AND_HIDDEN 1" >>confdefs.h
>  
>  
> +# Static PIE is supported.
> +$as_echo "#define SUPPORT_STATIC_PIE 1" >>confdefs.h
> +
> +
>  # We check to see if the compiler and flags are
>  # selecting the big endian ABI and if they are then
>  # we set libc_cv_aarch64_be to yes which causes

Skip since it is autogenerated.

> diff --git a/sysdeps/aarch64/configure.ac b/sysdeps/aarch64/configure.ac
> index 180a16a29f..66f755078a 100644
> --- a/sysdeps/aarch64/configure.ac
> +++ b/sysdeps/aarch64/configure.ac
> @@ -5,6 +5,9 @@ GLIBC_PROVIDES dnl See aclocal.m4 in the top level source directory.
>  # The exception is -mcmodel=large which is unsupported with PIC/PIE.
>  AC_DEFINE(PI_STATIC_AND_HIDDEN)
>  
> +# Static PIE is supported.
> +AC_DEFINE(SUPPORT_STATIC_PIE)
> +
>  # We check to see if the compiler and flags are
>  # selecting the big endian ABI and if they are then
>  # we set libc_cv_aarch64_be to yes which causes

Ok.

> diff --git a/sysdeps/i386/configure b/sysdeps/i386/configure
> index 90c63caf35..bb482ca16c 100644
> --- a/sysdeps/i386/configure
> +++ b/sysdeps/i386/configure
> @@ -117,3 +117,6 @@ if test x"$multi_arch" != xno; then
>    $as_echo "#define NO_HIDDEN_EXTERN_FUNC_IN_PIE 1" >>confdefs.h
>  
>  fi
> +
> +$as_echo "#define SUPPORT_STATIC_PIE 1" >>confdefs.h
> +

Skip since it is autogenerated.

> diff --git a/sysdeps/i386/configure.ac b/sysdeps/i386/configure.ac
> index 6d2068d2b3..5e43eb0adf 100644
> --- a/sysdeps/i386/configure.ac
> +++ b/sysdeps/i386/configure.ac
> @@ -77,3 +77,6 @@ dnl via PIC PLT in PIE, which requires setting up EBX register.
>  if test x"$multi_arch" != xno; then
>    AC_DEFINE(NO_HIDDEN_EXTERN_FUNC_IN_PIE)
>  fi
> +
> +dnl Static PIE is supported.
> +AC_DEFINE(SUPPORT_STATIC_PIE)

Ok.

> diff --git a/sysdeps/x86_64/configure b/sysdeps/x86_64/configure
> index 84f82c2406..198554d788 100644
> --- a/sysdeps/x86_64/configure
> +++ b/sysdeps/x86_64/configure
> @@ -143,5 +143,8 @@ fi
>  $as_echo "#define PI_STATIC_AND_HIDDEN 1" >>confdefs.h
>  
>  
> +$as_echo "#define SUPPORT_STATIC_PIE 1" >>confdefs.h
> +
> +
>  test -n "$critic_missing" && as_fn_error $? "
>  *** $critic_missing" "$LINENO" 5

Skip since it is autogenerated.

> diff --git a/sysdeps/x86_64/configure.ac b/sysdeps/x86_64/configure.ac
> index cdaba0c075..ec776274af 100644
> --- a/sysdeps/x86_64/configure.ac
> +++ b/sysdeps/x86_64/configure.ac
> @@ -82,5 +82,8 @@ dnl It is always possible to access static and hidden symbols in an
>  dnl position independent way.
>  AC_DEFINE(PI_STATIC_AND_HIDDEN)
>  
> +dnl Static PIE is supported.
> +AC_DEFINE(SUPPORT_STATIC_PIE)
> +
>  test -n "$critic_missing" && AC_MSG_ERROR([
>  *** $critic_missing])
> 

Ok.