Hi, thank You for quick answer.
I just realized that I am using LazBuild.exe for compiling because it allows using build modes:
%RegValueData%lazbuild.exe %~dp0\dll_A\dll_A.lpi --build-mode=Default
There ase 2 switches I haven't found what they mean:
-Scghi
-vewnhibq
Is using fpc.exe directly better?