Re: [PATCH 2/2] [gdb] Initialize main_thread_id earlier

[Tom Tromey <tom@tromey.com>]

>>>>> "Tom" == Tom de Vries via Gdb-patches <gdb-patches@sourceware.org> writes:

>> I wonder if it's enough to have:
>> static std::thread::id main_thread_id = std::this_thread::get_id ();

Tom> In principle it's enough but it does expose us to the "Static
Tom> Initialization Order Fiasco" [1], so I prefer this solution.

If we think it's safe enough to initialize it on first use, just moving
the definition into is_main_thread is enough to avoid this problem.

Now, in theory it is possible for gdb to start a thread very early and
then have that thread call is_main_thread, setting the global
incorrectly.  If we care about that then we need an explicit call to set
it early during startup.

Tom