Re: [PATCH] [gdb/build] Fix build breaker with -std=c++11

[John Baldwin <jhb@FreeBSD.org>]

On 8/7/23 4:11 PM, Tom de Vries wrote:
> On 8/7/23 20:01, John Baldwin wrote:
>> On 8/7/23 10:15 AM, Tom de Vries via Gdb-patches wrote:
>>> On 8/7/23 16:35, Simon Marchi wrote:
>>>>
>>>>
>>>> On August 6, 2023 7:59:15 p.m. EDT, Tom de Vries via Gdb-patches
>>>> <gdb-patches@sourceware.org> wrote:
>>>>> When building with -std=c++11 I run into:
>>>>> ...
>>>>> gdb/dwarf2/cooked-index.c: In member function \
>>>>>     ‘void cooked_index::start_writing_index(dwarf2_per_bfd*)’:
>>>>> gdb/dwarf2/cooked-index.c:469:10: error: lambda capture initializers
>>>>> only \
>>>>>     available with -std=c++14 or -std=gnu++14 [-Werror]
>>>>>             ctx = std::move (ctx)] ()
>>>>>             ^~~
>>>>> ...
>>>>>
>>>>> Fix this by capturing a copy instead:
>>>>> ...
>>>>>       = gdb::thread_pool::g_thread_pool->post_task ([this, per_bfd,
>>>>> ctx] ()
>>>>> ...
>>>>>
>>>>> Tested on x86_64-linux.
>>>>>
>>>>> Reported-By: Tom Tromey <tom@tromey.com>
>>>>
>>>> When we encounter things like this, should we add some greppable TODO
>>>> comment to record an actionable item for when we switch to a more
>>>> recent C++ version?
>>>
>>> Hi Simon,
>>>
>>> thanks for the review.
>>>
>>> Fine by me, added comment.
>>
>> An alternative that is slightly more work but might be nicer long term
>> would be
>> to #if on the C++ version, so for example:
>>
>> #if __cplusplus >= 201402L
>>     = gdb::thread_pool::g_thread_pool->post_task ([this, per_bfd,
>>                                                   ctx = std::move (ctx)] ()
>> #else
>>     = gdb::thread_pool::g_thread_pool->post_task ([this, per_bfd, ctx]) ()
>> #endif
>>
> 
> Thanks for the suggestion.  Updated patch attached.

LGTM

Reviewed-by: John Baldwin <jhb@FreeBSD.org>

-- 
John Baldwin