[PATCH] ld: Limit "readelf --got-contents" tests

[Jan Beulich]

On 04.09.2025 22:00, H.J. Lu wrote:
> On Thu, Sep 4, 2025 at 12:18 PM H.J. Lu <hjl.tools@gmail.com> wrote:
>>
>> On Thu, Sep 4, 2025 at 8:20 AM Rainer Orth <ro@cebitec.uni-bielefeld.de> wrote:
>>>
>>> Hi H.J.,
>>>
>>>>>>>> I want to make sure that --plt-contents displays all relevant
>>>>>>>> information correctly.  My tests are emulation specific.   There
>>>>>>>> is nothing Linux specific.
>>>>>>>
>>>>>>> Yet still the question stands - if it's just a few extra symbols, can't
>>>>>>> you cater for them using #?REGEXP constructs in the expectations?
>>>>>>
>>>>>> It sounds wrong.  Are you saying that the same emulation generates
>>>>>> extra symbols for Solaris?
>>>>>
>>>>> I'm not saying that, no, but see what Rainer said. Tests shouldn't be
>>>>> artificially restricted - the wider their coverage, the better.
>>>>>
>>>>
>>>> Please see the v2 patch:
>>>>
>>>> https://patchwork.sourceware.org/project/binutils/list/?series=51595
>>>
>>> I haven't tried it yet, but am pretty certain that it won't help:
>>>
>>> $  ./ld/ld-new -V
>>> GNU ld (GNU Binutils) 2.45.50.20250904
>>>   Supported emulations:
>>>    elf_x86_64_sol2
>>>    elf_x86_64
>>>    elf_i386_sol2
>>>    elf_i386_ldso
>>>    elf_i386
>>>    elf_iamcu
>>>
>>> Since the match isn't anchored it would also match the elf_*_sol2 lines.
>>
>> This is
>>
>> https://sourceware.org/bugzilla/show_bug.cgi?id=33374
>>
>>> Have you actually looked at my description and patch attached to the PR
>>> and the Solaris shared objects attached there for inspection?
>>
>> Will use
>>
>> # Tests here need -melf_i386 support.
>> set status [catch "exec $LD -V -melf_i386" got]
>> if { $status == 0 } {
>> ...
>> }
>>
>> in the v3 patch.
> 
> The "readelf --got-contents" tests check specific addresses to verify
> that "readelf --got-contents" works as expected.  Otherwise, we won't
> know that it stops working when these addresses are changed by
> accident.

Yet addresses changing isn't necessarily an indication of a problem. It
may or may not hint at there being one.

Jan