Re: [PATCH x86_64] Optimize access to globals in "-fpie -pie" builds with copy relocations

[Bernhard Reutner-Fischer <rep.dot.nop@gmail.com>]

On February 4, 2015 11:37:01 PM GMT+01:00, "H.J. Lu" <hjl.tools@gmail.com> wrote:
>On Wed, Feb 4, 2015 at 1:53 PM, Sriraman Tallam <tmsriram@google.com>
>wrote:
>> On Wed, Feb 4, 2015 at 10:57 AM, H.J. Lu <hjl.tools@gmail.com> wrote:
>>> On Wed, Feb 4, 2015 at 10:51 AM, Sriraman Tallam
><tmsriram@google.com> wrote:
>>>> On Wed, Feb 4, 2015 at 10:45 AM, H.J. Lu <hjl.tools@gmail.com>
>wrote:
>>>>> On Wed, Feb 4, 2015 at 10:42 AM, Jakub Jelinek <jakub@redhat.com>
>wrote:
>>>>>> On Wed, Feb 04, 2015 at 10:38:48AM -0800, H.J. Lu wrote:
>>>>>>> Common symbol should be resolved locally for PIE.
>>>>>>
>>>>>> binds_local_p yes, binds_to_current_def_p no.
>>>>>>
>>>>>
>>>>> Is SYMBOL_REF_LOCAL_P set to binds_local_p or
>>>>> binds_to_current_def_p?
>>>>
>>>> Looks like binds_local_p:
>>>>
>>>> varasm.c:
>>>> void
>>>> default_encode_section_info (tree decl, rtx rtl, int first
>ATTRIBUTE_UNUSED)
>>>> {
>>>>   ...
>>>>   if (targetm.binds_local_p (decl))
>>>>     flags |= SYMBOL_FLAG_LOCAL;
>>>>
>>>
>>> Why is SYMBOL_REF_LOCAL_P false?
>>
>> In varasm.c, default_binds_local_p_1
>>
>>
>>  /* Default visibility weak data can be overridden by a strong symbol
>>      in another module and so are not local.  */
>>   else if (DECL_WEAK (exp)
>>   && !resolved_locally)
>           ^^^^^^^^^^^^^^^^^^^
>Why is resolved_locally false? It should be true for common
>symbol when compiling for PIE.
>
>>     local_p = false;
>>
>> For weak definition, it is set to false here.

Yea and i think this is still wrong and known as 
http://gcc.gnu.org/PR32219

Thanks