qtcreator slowly consumes all system memory during "updating locator caches"

qtcreator-4.9.2 needs about 1GB memory and 1 minute to load my project, scan tree and parse sources.

qtcreator-4.10.0-b2 load the same project, scan tree and parse sources without problems but stuck in "updating locator caches". after few minutes it consumes >7GB of ram and hit the swap :/

gdb stacktrace attached.