Re: Gold bug in ordering text sections.

[Sriraman Tallam <tmsriram at google dot com>]

On Wed, Jan 16, 2013 at 2:33 PM, Ian Lance Taylor <iant@google.com> wrote:
> On Wed, Jan 16, 2013 at 2:27 PM, Sriraman Tallam <tmsriram@google.com> wrote:
>>
>>     This patch to gold : http://sourceware.org/ml/binutils/2012-12/msg00227.html
>> broke option --section-ordering-file and plugin based reordering. This
>> patch treats text sections as reorderable when special prefixes like
>> ".text.hot" are seen. However, when --section-ordering-file (or
>> plugins) is also used then it cannot override the default sorting as
>> the code in output.cc to do sorting checks for
>> "must_sort_attached_input_sections()" first and this is always true
>> for .text sections with those prefixes.
>>
>>    I have created the following patch to fix this. I have basically
>> disabled default sorting of .text sections in the presence of
>> --section-ordering-file or plugins. I think this makes sense because
>> this is also disabled in the presence of linker scripts.
>>
>>   One other alternative is to unset
>> "must_sort_attached_input_sections" for ".text" if
>> section-ordering-file or plugins do reorder ".text".  This can sort
>> .text sections by default if --section-ordering-file does not touch
>> any .text sections. I think this is overkill though.
>>
>>    This went unnoticed because none of the test cases generated the
>> special prefix for input text sections. I have modified the plugin
>> based test case to catch this problem. This test case will fail if the
>> patch to layout.cc is not present.
>
>
> This patch is OK.
>
> Thanks.

Thanks, this patch is now committed.

Sri

>
> Ian