Trying out Lazarus but after 15.4 , many folk are running into problems compiling. Im one of them.
(I have a working install on my Windows machine, but … well.. I prefer working on my Macbook)
Any lazarus people here?
Lazarus ja, but GNU/LInux, not Mac 
try running the lazarus executable in the folder, not the .app
the .app thinks its corrupted but the executable works just fine, and the .app seems to be just a link to it.
Got it working now, cheers.
Biggest issue was having to add -WM10.15
Into the custom compiler options of every project. No actual idea what it does, but all working fine now.
That should be the minimum deployment target, Catalina.