Re: [Qemu-devel] [PATCH v3 07/28] build-sys: must link with -fstack-protector

[Laurent Desnogues]

Hi,

Another issue on my old distro.

On Mon, Apr 22, 2013 at 5:04 PM, Alon Levy <address@hidden> wrote:
> From: Marc-André Lureau <address@hidden>
>
> It is needed to give that flag to the linker as well, but latest
> libtool 2.4.2 still swallows that argument, so let's pass it with
> libtool -Wc argument.
>
> qemu-1.4.0/stubs/arch-query-cpu-def.c:6: undefined reference to 
> `__stack_chk_guard'
>
> Signed-off-by: Marc-André Lureau <address@hidden>
> ---
>  configure | 8 +++++++-
>  rules.mak | 1 +
>  2 files changed, 8 insertions(+), 1 deletion(-)
>
> diff --git a/configure b/configure
> index ed49f91..dcc4767 100755
> --- a/configure
> +++ b/configure
> @@ -1238,7 +1238,7 @@ fi
>  gcc_flags="-Wold-style-declaration -Wold-style-definition -Wtype-limits"
>  gcc_flags="-Wformat-security -Wformat-y2k -Winit-self -Wignored-qualifiers 
> $gcc_flags"
>  gcc_flags="-Wmissing-include-dirs -Wempty-body -Wnested-externs $gcc_flags"
> -gcc_flags="-fstack-protector-all -Wendif-labels $gcc_flags"
> +gcc_flags="-Wendif-labels $gcc_flags"
>  gcc_flags="-Wno-initializer-overrides $gcc_flags"
>  # Note that we do not add -Werror to gcc_flags here, because that would
>  # enable it for all configure tests. If a configure test failed due
> @@ -1257,6 +1257,11 @@ for flag in $gcc_flags; do
>      fi
>  done
>
> +if compile_prog "-Werror -fstack-protector-all" "" ; then
> +    QEMU_CFLAGS="$QEMU_CFLAGS -fstack-protector-all"
> +    LIBTOOLFLAGS="$LIBTOOLFLAGS -Wc,-fstack-protector-all"

With that LIBTOOLFLAGS, libtool makes a call to cc with
-Wl,-fstack-protector-all which in my case fails:

/usr/bin/ld: -f may not be used without -shared

I don't know where the issue comes from, libtool or ld.  Here are the
versions I have:

libtool-1.5.22-7.el5_4
binutils-2.17.50.0.6-14.el5

Thanks,

Laurent

> +fi
> +
>  # Workaround for http://gcc.gnu.org/PR55489.  Happens with -fPIE/-fPIC and
>  # large functions that use global variables.  The bug is in all releases of
>  # GCC, but it became particularly acute in 4.6.x and 4.7.x.  It is fixed in
> @@ -4068,6 +4073,7 @@ else
>    echo "AUTOCONF_HOST := "                             >> $config_host_mak
>  fi
>  echo "LDFLAGS=$LDFLAGS" >> $config_host_mak
> +echo "LIBTOOLFLAGS=$LIBTOOLFLAGS" >> $config_host_mak
>  echo "LIBS+=$LIBS" >> $config_host_mak
>  echo "LIBS_TOOLS+=$libs_tools" >> $config_host_mak
>  echo "EXESUF=$EXESUF" >> $config_host_mak
> diff --git a/rules.mak b/rules.mak
> index edc2552..36aba2d 100644
> --- a/rules.mak
> +++ b/rules.mak
> @@ -36,6 +36,7 @@ LINK = $(call quiet-command,\
>         $(if $(filter %.lo %.la,$^),$(LIBTOOL) --mode=link --tag=CC \
>         )$(CC) $(QEMU_CFLAGS) $(CFLAGS) $(LDFLAGS) -o $@ \
>         $(sort $(filter %.o, $1)) $(filter-out %.o, $1) $(version-obj-y) \
> +       $(if $(filter %.lo %.la,$^),$(LIBTOOLFLAGS)) \
>         $(LIBS),$(if $(filter %.lo %.la,$^),"lt LINK ", "  LINK  
> ")"$(TARGET_DIR)$@")
>  endif
>
> --
> 1.8.2
>
>