[Lazarus] Can I be sure that timer and synchronize never fire at once?

[Luca Olivetti]

Hello,
I'm trying to debug a strange crash in an application (it's strange 
because the exception dialog appears and then disappears almost 
instantly without clicking on any button, so the customer cannot tell me 
the reason of the exception).

My application (as almost any application I write) is based on the 
assumption that methods invoked by a timer and methods invoked by a 
thread with synchronize will never fire at once (i.e. they will be 
serialized by the main loop).

Can I be 100% sure of that?
I'm currently using an old version of lazarus (svn 22953 dated 
2009-12-04) with fpc 2.2.4.

Bye
-- 
Luca Olivetti
Wetron Automatización S.A. http://www.wetron.es/
Tel. +34 93 5883004 (Ext.133)  Fax +34 93 5883007