[PATCH 2/2] manual: Document __libc_single_threaded

[Florian Weimer]

* Szabolcs Nagy:

> The 05/20/2020 20:12, Florian Weimer via Libc-alpha wrote:
>> +@smallexample
>> +if (__libc_single_threaded)
>> +  atomic_fetch_add (&reference_count, 1, memory_order_relaxed);
>> +else
>> +  atomic_fetch_add (&reference_count, 1, memory_order_acq_rel);
>> +@end smallexample
>> +
>> +This still requires some form of synchronization on the
>> +single-threaded branch, so it can be beneficial not to declare the
>> +reference count as @code{_Atomic}, and use the GCC @code{__atomic}
>> +built-ins.  @xref{__atomic Builtins,, Built-in Functions for Memory
>> +Model Aware Atomic Operations, gcc, Using the GNU Compiler Collection
>> +(GCC)}.  Then the code to increment a reference count looks like this:
>> +
>> +@smallexample
>> +if (__libc_single_threaded)
>> +  ++refeference_count;inf
>
> inf typo

Thanks, queued for V2.

Florian