Re: Pretest?

["Jan Djärv" <jan.h.d@swipnet.se>]

Jan Djärv skrev:
> 
> 
> YAMAMOTO Mitsuharu skrev:
>>>>>>> On Thu, 15 Mar 2007 12:04:33 +0100, Jan Djärv 
>>>>>>> <jan.h.d@swipnet.se> said:
>>
>>>> I suspect src/gmalloc.c, which does not provide thread-safe malloc
>>>> (correct me if I'm wrong), is used while HAVE_GTK_AND_PTHREAD is
>>>> defined.
>>
>>> If src/gmalloc.c is used, then the hooks in alloc.c are used, so
>>> they should be thread safe.
>>
>> No, alloc_mutex only protects the variables __malloc_hook etc., but
>> not for the heap itself.  Consider the following scenario:
>>
>>   1) The main thread calls malloc.
>>   2) It then calls emacs_blocked_malloc via __malloc_hook.
>>   3) __malloc_hook is set to old_malloc_hook in emacs_blocked_malloc.
>>   4) Now the main thread is in execution of the original malloc.
>>   5) Another thread also calls malloc.
>>   6) The thread also executes the original malloc because
>>      __malloc_hook == old_malloc_hook.
> 
> You are correct.  Can we, should we fix this, i.e. make gmalloc.c thread 
> safe?
> 

A thing to do after the release might be to synchronize with the thread safe 
malloc in glibc.

	Jan D.