testmutexscope failure under mingw

[Andrew Teirney <an...@teirney.net>]

Hi All,

I've just been working on getting the mingw build of apr up and running 
(based on trunk@r464899), it all seems to go well and i get the compiled 
libraries as expected.

However when it comes to testing i notice that there are problems such 
that the testmutexscope.exe fails. The output is as follows.

<quote>
Trying proc mutexes with mechanism `default'...
   Mutex mechanism `default' is global in scope on this platform.
Assertion failed: rv == APR_SUCCESS, file testmutexscope.c, line 169

This application has requested the Runtime to terminate it in an unusual 
way. Please contact the application's support team for more information.
</quote>

Basically what appears to be happening in that the apr_thread_join 
returns APR_INCOMPLETE, this is correct as per the apr_thread_join 
source code as the thread's pool is still intact (apr_thread_exit was 
not called for thread cleanup). However the thread itself has exited, or 
more rather then threads main function has returned.

My question comes down to the usage of apr_thread_exit(...), should all 
threads prior to returning call this function, and if it does not then 
is it considered a usage error? I would be inclined to change the dummy 
thread function such that if the threads function registered via 
apr_thread_create does return then apr_thread_exit(...) is called, 
however this is more a fail safe for perhaps incorrect usage?

I myself did try to assertain whether apr_thread_exit() was infact 
required to be called, however i failed and looking at the test examples 
they generally do not.

Andrew