Unable to build or save edited file because clangbackend.exe is using it

After successfully renaming symbols with Ctrl + Shift + R, I am sometimes unable to save the files that were edited because clangbackend.exe is using those files. Therefore this bug also prevents me to build my project.

Sometimes clangbackend releases the file very quickly, but most of the times I cannot save them until a couple of minutes have passed. When this happens, Qt Creator shows the "File Error" popup stating that the disk is full (see attached screenshot). It seems to happen mostly with header files.

I have checked with a process utility that it is indeed clangbackend that has handles on the files. If I kill the process I can save files and build again.

Also as reported in other bugs, the clang analyser slows down a lot auto competition, color highlighting and other stuff.
But it's a very useful feature so I'm looking forward to its improvement!