On Wed, Mar 18, 2015 at 4:56 AM, Ilya Enkovich <enkovich....@gmail.com> wrote:
> Hi,
>
> This patch fixes PR target/65444 by passing '-z bndplt' to linker when
> appropriate. Bootstrapped and tested on x86_64-unknown-linux-gnu. Will
> commit it to trunk in a couple of days if no objections arise.
>
> Thanks,
> Ilya
> --
> gcc/
>
> 2015-03-18 Ilya Enkovich <ilya.enkov...@intel.com>
>
> PR driver/65444
> * config/i386/linux-common.h (MPX_SPEC): New.
> (CHKP_SPEC): Add MPX_SPEC.
>
> libmpx/
>
> 2015-03-18 Ilya Enkovich <ilya.enkov...@intel.com>
>
> PR driver/65444
> * configure.ac: Add check for '-z bndplt' support
> by linker. Add link_mpx output variable.
> * libmpx.spec.in (link_mpx): New.
> * configure: Regenerate.
>
>
> diff --git a/gcc/config/i386/linux-common.h b/gcc/config/i386/linux-common.h
> index 9c6560b..dd79ec6 100644
> --- a/gcc/config/i386/linux-common.h
> +++ b/gcc/config/i386/linux-common.h
> @@ -59,6 +59,11 @@ along with GCC; see the file COPYING3. If not see
> %:include(libmpx.spec)%(link_libmpx)"
> #endif
>
> +#ifndef MPX_SPEC
> +#define MPX_SPEC "\
> +
> %{mmpx:%{fcheck-pointer-bounds:%{!static:%:include(libmpx.spec)%(link_mpx)}}}"
> +#endif
> +
> #ifndef LIBMPX_SPEC
> #if defined(HAVE_LD_STATIC_DYNAMIC)
> #define LIBMPX_SPEC "\
> @@ -89,5 +94,5 @@ along with GCC; see the file COPYING3. If not see
>
> #ifndef CHKP_SPEC
> #define CHKP_SPEC "\
> -%{!nostdlib:%{!nodefaultlibs:" LIBMPX_SPEC LIBMPXWRAPPERS_SPEC "}}"
> +%{!nostdlib:%{!nodefaultlibs:" LIBMPX_SPEC LIBMPXWRAPPERS_SPEC "}}" MPX_SPEC
> #endif
> diff --git a/libmpx/configure.ac b/libmpx/configure.ac
> index fe0d3f2..3f8b50f 100644
> --- a/libmpx/configure.ac
> +++ b/libmpx/configure.ac
> @@ -40,7 +40,18 @@ AC_MSG_RESULT($LIBMPX_SUPPORTED)
> AM_CONDITIONAL(LIBMPX_SUPPORTED, [test "x$LIBMPX_SUPPORTED" = "xyes"])
>
> link_libmpx="-lpthread"
> +link_mpx=""
> +AC_MSG_CHECKING([whether ld accepts -z bndplt])
> +echo "int main() {};" > conftest.c
> +if AC_TRY_COMMAND([${CC} ${CFLAGS} -Wl,-z,bndplt -o conftest conftest.c
> 1>&AS_MESSAGE_LOG_FD])
> +then
> + AC_MSG_RESULT([yes])
> + link_mpx="$link_mpx -z bndplt"
> +else
> + AC_MSG_RESULT([no])
> +fi
> AC_SUBST(link_libmpx)
> +AC_SUBST(link_mpx)
>
Without -z bndplt, MPX won't work correctly. We should always pass -z bndplt
to linker. If linker doesn't support it, ld will issue a warning, not
error and users
will know their linker is too old. When they update linker, they don't have to
rebuild GCC.
--
H.J.
