Today my Delphi went ape. At a moment I recompiled and run a program. FastMM started to report all kind of strange memory leaks but it was unable to locate the source of the error (unknown address). After a while I tried disabling FastMM and recompiling the program. The program was recompiled but it had no icon.
Solution:
After a long trial and error session I have found that rebuilding my VCLs solved the issue.
It seems that even if my VCLs are set to “rebuild as needed’ Delphi recompiles their DCUs but not also the afferent BPL/DCP files.