A few days ago, when the C Builder6.0 installation component package (with Delphi unit files), the report Linker Error: The specific information is as follows:
[Linker Error] unresolved External '__fastcall Outline :: Tcustomoutline :: ~ tcustomoutline ()' Reference from ...
Later, I came online and finally found a solution:
Add BCBSMP.BPI in the component package (Requires section).
Path: $ (BCB) /LIB/BCBSMP.BPI