Re: [PATCH, libmpx, i386, PR driver/65444] Pass '-z bndplt' when building dynamic objects with MPX

[Jeff Law <law@redhat.com>]

On 05/26/2015 03:13 AM, Ilya Enkovich wrote:
> On 06 Apr 09:28, Jeff Law wrote:
>> On 04/06/2015 09:17 AM, Ilya Enkovich wrote:
>>>>
>>>> To tell the truth, I can't figure out what this means from a user
>>>> perspective.  How does a user know whether the linker option is
>>>> being ignored, or if they have a new enough linker?  If the linker
>>>> available at configuration time doesn't support the option, does
>>>> that mean the option will never be passed and users will never know
>>>> that there are gaping holes in the pointer bounds checking?
>>>>
>>>> My suggestion would be to pass the option unconditionally and make
>>>> the documentation say something like
>>>
>>> This option was rejected.
>> Right.  There really isn't a good option here because we don't have
>> the infrastructure to query the linker's capabilities at link time.
>>
>> Though I do wonder if we could issue a warning in the case where the
>> configure test indicated -z bndplt was not supported.
>>
>> It'd obviously mean a link warning every time an end user tried to
>> use that toolchain to create a DSO or executable with MPX
>> protection.  But that may be better than silently leaving some code
>> unprotected.
>>
>>
>> Jeff
>>
>
> Hi,
>
> Here is a patch to add a note in case we build dynamic MPX codes and don't pass '-z bndplt'.  Does it look OK?
>
> Thanks,
> Ilya
> --
> gcc/
>
> 2015-05-26  Ilya Enkovich  <enkovich.gnu@gmail.com>
>
> 	* config/i386/linux-common.h (MPX_SPEC): Add link
> 	warning.
>
> libmpx/
>
> 2015-05-26  Ilya Enkovich  <enkovich.gnu@gmail.com>
>
> 	* configure.ac: Add link_mpx_warning.
> 	* libmpx.spec.in: Likewise.
> 	* configure: Regenerate.
Is there a way to do this outside of the specs mechanism?  If done in 
the specs, are these warnings translated for locales?

Jeff