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Re: [PATCH][BZ #13724] Do not segfault in pthread_setname_np (x, NULL)

On 10/08/2013 12:45 PM, Andreas Schwab wrote:
> "Carlos O'Donell" <> writes:
>> Should we have an assert there then to document the contract and provide
>> a more meaningful error message like a backtrace?
> Asseertions are for internal consistency checking, but this is an
> external condition.

So you're saying that the external conditions are governed solely
by the API and that violating the API by passing a NULL value leads
to undefined behaviour?

In this case the error is immediate as strlen segfaults. I'm happy
with that since it's easy to debug.

However, I'm not happy that this consensus may lead to errors that
are not near the point at which the application enters into 
undefined behaviour.

I've documented what I understand is our practice for assert:
Assertions are for internal consistency checking only.

External conditions are governed by the API and if user 
code violates the API then the library behaviour is undefined.

However, in scenarios where user input is recorded into 
internal structures for later use it is useful to assert 
in these cases to catch the first occurrence of the error. 


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