Hoping that it help somebody by posting it here.
The subject line is the error I see when compiling about once every 2 days.
Once that happens the only thing that I found so far that resolves it is to reboot my computer.
Restarting the Delphi Studio is not enough.
I have no idea what causes it, but my best guess is that some file gets locked and that the linker can not write to it anymore.
Am now wondering if it would help to delete all the files in the OSX64/debug folder.
Next time I will try that.