Went to <Settings><Editor...><Code Completion><Symbols Browser page> and checked "Disable Symbols Browser" <Ok>.
Ah, I see now.
Well, this time, I disabled symbols browser this way, opened a project (a trivial C++ console application) then again tried to open a .c file that does not belong to this project. C::B hung, like it did before. I tried this both with and without ThreadSanitizer being active, the results are the same.
The log of C::B (cb04.log) and a part of ThreadSanitizer report (tsan-cb04-hybrid.log) are in the attached archive. The race detector still reports some possible data races that could be related to code completion component. I cannot say whether they are real races or whether they are related to this very problem.
What are your settings for codecompletion (parser) and symbols browser ?
Jens, I use the default settings. Except for disabling symbols browser, I have not changed the settings since I have build C::B (rev. 7406, built on Ubuntu 10.04 x86-64) the first time. default.conf from my system is also in the attached archive, just in case (it is a copy of ~/.codeblocks/default.conf, there were no other .conf files there).