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Subject: Re: Compiling C++ modules
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Dmitry Torokhov wrote:
>>>     TakeLock l(&lock);
>>>
>>>     do_something();
>>>     do_something_else();
>>>
>>> First of all, that extra TakeLock object chews up stack, at least 4 or
>>> 8 bytes of it, depending on your word size.
>>>       
>> No, it's optimized out. gcc notices that &lock doesn't change and that
>> 'l' never escapes the function.
>>     
>
> "l" that propects critical section gets thrown away??? 
Calm down, the storage for 'l' is thrown away, but its effects remain.
> What is the
> name of the filesystem you ported? I mean, I need to know so I don't
> use it by accident.
>   
It's very expensive, you can't use it by accident.

-- 
Do not meddle in the internals of kernels, for they are subtle and quick to panic.